diff --git a/reference/yar/versions.xml b/reference/yar/versions.xml
index 38eff949b5..2077837b8d 100644
--- a/reference/yar/versions.xml
+++ b/reference/yar/versions.xml
@@ -6,113 +6,113 @@
 
 <versions>
   <!-- Methods -->
- <function name='yar_server::__construct' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server::handle' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client::__construct' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client::call' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client::__call' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client::setopt' from='PECL yar &gt;= Unknown'/>
- <function name='yar_concurrent_client::call' from='PECL yar &gt;= Unknown'/>
- <function name='yar_concurrent_client::loop' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_exception::gettype' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_exception::__clone' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_exception::__construct' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_exception::getmessage' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_exception::getcode' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_exception::getfile' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_exception::getline' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_exception::gettrace' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_exception::getprevious' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_exception::gettraceasstring' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_exception::__tostring' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_request_exception::gettype' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_request_exception::__clone' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_request_exception::__construct' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_request_exception::getmessage' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_request_exception::getcode' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_request_exception::getfile' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_request_exception::getline' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_request_exception::gettrace' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_request_exception::getprevious' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_request_exception::gettraceasstring' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_request_exception::__tostring' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_protocol_exception::gettype' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_protocol_exception::__clone' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_protocol_exception::__construct' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_protocol_exception::getmessage' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_protocol_exception::getcode' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_protocol_exception::getfile' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_protocol_exception::getline' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_protocol_exception::gettrace' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_protocol_exception::getprevious' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_protocol_exception::gettraceasstring' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_protocol_exception::__tostring' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_packager_exception::gettype' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_packager_exception::__clone' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_packager_exception::__construct' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_packager_exception::getmessage' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_packager_exception::getcode' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_packager_exception::getfile' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_packager_exception::getline' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_packager_exception::gettrace' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_packager_exception::getprevious' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_packager_exception::gettraceasstring' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_packager_exception::__tostring' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_output_exception::gettype' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_output_exception::__clone' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_output_exception::__construct' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_output_exception::getmessage' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_output_exception::getcode' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_output_exception::getfile' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_output_exception::getline' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_output_exception::gettrace' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_output_exception::getprevious' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_output_exception::gettraceasstring' from='PECL yar &gt;= Unknown'/>
- <function name='yar_server_output_exception::__tostring' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_exception::gettype' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_exception::__clone' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_exception::__construct' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_exception::getmessage' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_exception::getcode' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_exception::getfile' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_exception::getline' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_exception::gettrace' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_exception::getprevious' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_exception::gettraceasstring' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_exception::__tostring' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_transport_exception::gettype' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_transport_exception::__clone' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_transport_exception::__construct' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_transport_exception::getmessage' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_transport_exception::getcode' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_transport_exception::getfile' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_transport_exception::getline' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_transport_exception::gettrace' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_transport_exception::getprevious' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_transport_exception::gettraceasstring' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_transport_exception::__tostring' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_packager_exception::gettype' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_packager_exception::__clone' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_packager_exception::__construct' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_packager_exception::getmessage' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_packager_exception::getcode' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_packager_exception::getfile' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_packager_exception::getline' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_packager_exception::gettrace' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_packager_exception::getprevious' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_packager_exception::gettraceasstring' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_packager_exception::__tostring' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_protocol_exception::gettype' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_protocol_exception::__clone' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_protocol_exception::__construct' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_protocol_exception::getmessage' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_protocol_exception::getcode' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_protocol_exception::getfile' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_protocol_exception::getline' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_protocol_exception::gettrace' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_protocol_exception::getprevious' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_protocol_exception::gettraceasstring' from='PECL yar &gt;= Unknown'/>
- <function name='yar_client_protocol_exception::__tostring' from='PECL yar &gt;= Unknown'/>
+ <function name='yar_server::__construct' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server::handle' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client::__construct' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client::call' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client::__call' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client::setopt' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_concurrent_client::call' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_concurrent_client::loop' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_exception::gettype' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_exception::__clone' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_exception::__construct' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_exception::getmessage' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_exception::getcode' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_exception::getfile' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_exception::getline' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_exception::gettrace' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_exception::getprevious' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_exception::gettraceasstring' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_exception::__tostring' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_request_exception::gettype' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_request_exception::__clone' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_request_exception::__construct' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_request_exception::getmessage' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_request_exception::getcode' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_request_exception::getfile' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_request_exception::getline' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_request_exception::gettrace' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_request_exception::getprevious' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_request_exception::gettraceasstring' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_request_exception::__tostring' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_protocol_exception::gettype' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_protocol_exception::__clone' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_protocol_exception::__construct' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_protocol_exception::getmessage' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_protocol_exception::getcode' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_protocol_exception::getfile' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_protocol_exception::getline' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_protocol_exception::gettrace' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_protocol_exception::getprevious' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_protocol_exception::gettraceasstring' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_protocol_exception::__tostring' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_packager_exception::gettype' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_packager_exception::__clone' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_packager_exception::__construct' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_packager_exception::getmessage' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_packager_exception::getcode' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_packager_exception::getfile' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_packager_exception::getline' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_packager_exception::gettrace' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_packager_exception::getprevious' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_packager_exception::gettraceasstring' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_packager_exception::__tostring' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_output_exception::gettype' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_output_exception::__clone' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_output_exception::__construct' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_output_exception::getmessage' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_output_exception::getcode' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_output_exception::getfile' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_output_exception::getline' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_output_exception::gettrace' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_output_exception::getprevious' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_output_exception::gettraceasstring' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_server_output_exception::__tostring' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_exception::gettype' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_exception::__clone' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_exception::__construct' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_exception::getmessage' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_exception::getcode' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_exception::getfile' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_exception::getline' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_exception::gettrace' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_exception::getprevious' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_exception::gettraceasstring' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_exception::__tostring' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_transport_exception::gettype' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_transport_exception::__clone' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_transport_exception::__construct' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_transport_exception::getmessage' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_transport_exception::getcode' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_transport_exception::getfile' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_transport_exception::getline' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_transport_exception::gettrace' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_transport_exception::getprevious' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_transport_exception::gettraceasstring' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_transport_exception::__tostring' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_packager_exception::gettype' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_packager_exception::__clone' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_packager_exception::__construct' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_packager_exception::getmessage' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_packager_exception::getcode' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_packager_exception::getfile' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_packager_exception::getline' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_packager_exception::gettrace' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_packager_exception::getprevious' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_packager_exception::gettraceasstring' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_packager_exception::__tostring' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_protocol_exception::gettype' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_protocol_exception::__clone' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_protocol_exception::__construct' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_protocol_exception::getmessage' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_protocol_exception::getcode' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_protocol_exception::getfile' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_protocol_exception::getline' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_protocol_exception::gettrace' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_protocol_exception::getprevious' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_protocol_exception::gettraceasstring' from='PECL yar &gt;= 1.0.0'/>
+ <function name='yar_client_protocol_exception::__tostring' from='PECL yar &gt;= 1.0.0'/>
 </versions>
 
 <!-- Keep this comment at the end of the file
diff --git a/reference/yar/yar_client/setopt.xml b/reference/yar/yar_client/setopt.xml
index f6cc6eb1f2..bd0b4f6678 100644
--- a/reference/yar/yar_client/setopt.xml
+++ b/reference/yar/yar_client/setopt.xml
@@ -61,9 +61,13 @@
 <?php
 
 $cient = new Yar_Client("http://host/api/");
+
 //Set timeout to 1s
 $client->SetOpt(YAR_OPT_CONNECT_TIMEOUT, 1000);
 
+//Set packager to JSON
+$client->SetOpt(YAR_OPT_PACKAGER, "json");
+
 /* call remote service */
 $result = $client->some_method("parameter");
 ?>
diff --git a/reference/yar/yar_concurrent_client/call.xml b/reference/yar/yar_concurrent_client/call.xml
index 21868467e8..4a7d1143dd 100644
--- a/reference/yar/yar_concurrent_client/call.xml
+++ b/reference/yar/yar_concurrent_client/call.xml
@@ -10,7 +10,7 @@
  <refsect1 role="description">
   &reftitle.description;
   <methodsynopsis>
-   <modifier>public</modifier> <modifier>static</modifier> <type>void</type><methodname>Yar_Concurrent_Client::call</methodname>
+   <modifier>public</modifier> <modifier>static</modifier> <type>int</type><methodname>Yar_Concurrent_Client::call</methodname>
    <methodparam><type>string</type><parameter>uri</parameter></methodparam>
    <methodparam><type>string</type><parameter>method</parameter></methodparam>
    <methodparam><type>array</type><parameter>parameters</parameter></methodparam>
@@ -29,7 +29,7 @@
     <term><parameter>uri</parameter></term>
     <listitem>
      <para>
-      
+       The RPC server URI(http, tcp)
      </para>
     </listitem>
    </varlistentry>
@@ -37,7 +37,7 @@
     <term><parameter>method</parameter></term>
     <listitem>
      <para>
-      
+      Service name(aka the method name)
      </para>
     </listitem>
    </varlistentry>
@@ -45,7 +45,7 @@
     <term><parameter>parameters</parameter></term>
     <listitem>
      <para>
-      
+      Parameters
      </para>
     </listitem>
    </varlistentry>
@@ -53,7 +53,7 @@
     <term><parameter>callback</parameter></term>
     <listitem>
      <para>
-      
+      A function callback, which will be called while the response return.
      </para>
     </listitem>
    </varlistentry>
@@ -63,7 +63,7 @@
  <refsect1 role="returnvalues">
   &reftitle.returnvalues;
   <para>
-
+   An unique id, can be used to identified which call it is.
   </para>
  </refsect1>
 
diff --git a/reference/yar/yar_concurrent_client/loop.xml b/reference/yar/yar_concurrent_client/loop.xml
index f7e44d5d67..de2e19d3cf 100644
--- a/reference/yar/yar_concurrent_client/loop.xml
+++ b/reference/yar/yar_concurrent_client/loop.xml
@@ -26,7 +26,13 @@
     <term><parameter>callback</parameter></term>
     <listitem>
      <para>
-      
+      If this callback is set, then Yar will call this callback after all
+      calls are sent and before any response return, with a $callinfo NULL.
+     </para>
+     <para>
+      Then, if user didn't specify callback when registering concurrent call,
+      this callback will be used to handle response, otherwise, the callback
+      specified while registering will be used.
      </para>
     </listitem>
    </varlistentry>
@@ -34,7 +40,8 @@
     <term><parameter>error_callback</parameter></term>
     <listitem>
      <para>
-      
+      If this callback is set, then Yar will call this callback while error
+      occurred.
      </para>
     </listitem>
    </varlistentry>
@@ -61,8 +68,13 @@
 <![CDATA[
 <?php
 function callback($retval, $callinfo) {
-     var_dump($retval);
-}
+     if ($callinfo == NULL) {
+        echo "Now, all requests are sent, and no any response available";
+     } else {
+        echo "This is a remote call response, the method name is", $callinfo["method"];
+        var_dump($retval);
+     }
+} 
 
 function error_callback($type, $error, $callinfo) {
     error_log($error);
diff --git a/reference/yar/yar_server/construct.xml b/reference/yar/yar_server/construct.xml
index a2cbb33b78..bfd659b50b 100644
--- a/reference/yar/yar_server/construct.xml
+++ b/reference/yar/yar_server/construct.xml
@@ -4,7 +4,7 @@
 <refentry xml:id="yar-server.construct" xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink">
  <refnamediv>
   <refname>Yar_Server::__construct</refname>
-  <refpurpose>The __construct purpose</refpurpose>
+  <refpurpose>Register a server</refpurpose>
  </refnamediv>
 
  <refsect1 role="description">
@@ -12,7 +12,6 @@
   <methodsynopsis>
    <modifier>final</modifier> <modifier>public</modifier> <methodname>Yar_Server::__construct</methodname>
    <methodparam><type>Object</type><parameter>obj</parameter></methodparam>
-   <methodparam choice="opt"><type>string</type><parameter>protocol</parameter></methodparam>
   </methodsynopsis>
   <para>
    Set up a Yar HTTP RPC Server, All the public methods of $obj will be
@@ -32,14 +31,6 @@
      </para>
     </listitem>
    </varlistentry>
-   <varlistentry>
-    <term><parameter>protocol</parameter></term>
-    <listitem>
-     <para>
-      
-     </para>
-    </listitem>
-   </varlistentry>
   </variablelist>
  </refsect1>