diff --git a/reference/http/constants.xml b/reference/http/constants.xml
index 0bac965e3f..1481865882 100644
--- a/reference/http/constants.xml
+++ b/reference/http/constants.xml
@@ -1,5 +1,5 @@
 <?xml version='1.0' encoding='iso-8859-1'?>
-<!-- $Revision: 1.3 $ -->
+<!-- $Revision: 1.4 $ -->
 <refentry id="http.constants">
  <refnamediv>
   <refname>Constants</refname>
@@ -595,6 +595,17 @@
      </simpara>
     </listitem>
    </varlistentry>
+   <varlistentry>
+    <term>
+     <constant>HTTP_AUTH_GSSNEG</constant>
+      (<type>integer</type>)
+    </term>
+    <listitem>
+     <simpara>
+      use &quot;GSS-NEGOTIATE&quot; authentication
+     </simpara>
+    </listitem>
+   </varlistentry>
    <varlistentry>
     <term>
      <constant>HTTP_AUTH_ANY</constant>
@@ -611,7 +622,7 @@
    <title>Constants used for the HTTP <literal>protocol</literal> version &link.http.request.option;</title>
    <varlistentry>
     <term>
-     <constant>HTTP_VERSION_ANY</constant>
+     <constant>HTTP_VERSION_ANY</constant> <!-- HTTP_VERSION_NONE is deprecated -->
       (<type>integer</type>)
     </term>
     <listitem>
@@ -643,6 +654,53 @@
     </listitem>
    </varlistentry>
   </variablelist>
+  <variablelist id="http.constants.request.ssl">
+   <title>Constants used for the SSL <literal>protocol</literal> type and version &link.http.request.option;</title>
+   <varlistentry>
+    <term>
+     <constant>HTTP_SSL_VERSION_ANY</constant>
+      (<type>integer</type>)
+    </term>
+    <listitem>
+     <simpara>
+      no specific SSL protocol version
+     </simpara>
+    </listitem>
+   </varlistentry>
+   <varlistentry>
+    <term>
+     <constant>HTTP_SSL_VERSION_TLSv1</constant>
+      (<type>integer</type>)
+    </term>
+    <listitem>
+     <simpara>
+      use TLSv1 only
+     </simpara>
+    </listitem>
+   </varlistentry>
+   <varlistentry>
+    <term>
+     <constant>HTTP_SSL_VERSION_SSLv3</constant>
+      (<type>integer</type>)
+    </term>
+    <listitem>
+     <simpara>
+      use SSLv3 only
+     </simpara>
+    </listitem>
+   </varlistentry>
+   <varlistentry>
+    <term>
+     <constant>HTTP_SSL_VERSION_SSLv2</constant>
+      (<type>integer</type>)
+    </term>
+    <listitem>
+     <simpara>
+      use SSLv2 only
+     </simpara>
+    </listitem>
+   </varlistentry>
+  </variablelist>
   <variablelist id="http.constants.request.proxy">
    <title>Constants used for the <literal>proxytype</literal> &link.http.request.option;</title>
    <varlistentry>
@@ -679,6 +737,42 @@
     </listitem>
    </varlistentry>
   </variablelist>
+  <variablelist id="http.constants.request.dns">
+   <title>Constants affecting name lookups (DNS)</title>
+   <varlistentry>
+    <term>
+     <constant>HTTP_IPRESOLVE_V4</constant>
+      (<type>integer</type>)
+    </term>
+    <listitem>
+     <simpara>
+      use IPv4 only for name lookups
+     </simpara>
+    </listitem>
+   </varlistentry>
+   <varlistentry>
+    <term>
+     <constant>HTTP_IPRESOLVE_V6</constant>
+      (<type>integer</type>)
+    </term>
+    <listitem>
+     <simpara>
+      use IPv6 only for name lookups
+     </simpara>
+    </listitem>
+   </varlistentry>
+   <varlistentry>
+    <term>
+     <constant>HTTP_IPRESOLVE_ANY</constant>
+      (<type>integer</type>)
+    </term>
+    <listitem>
+     <simpara>
+      use any IP mechanism only for name lookups
+     </simpara>
+    </listitem>
+   </varlistentry>
+  </variablelist>
   <variablelist id="http.constants.request.methods">
    <title>Predefined HTTP request method constants</title>
    <varlistentry>