diff --git a/reference/errorfunc/functions/set-error-handler.xml b/reference/errorfunc/functions/set-error-handler.xml
index 51ef8fd05e..da0038de8f 100644
--- a/reference/errorfunc/functions/set-error-handler.xml
+++ b/reference/errorfunc/functions/set-error-handler.xml
@@ -75,7 +75,7 @@
       </para>
       <para>
        <methodsynopsis>
-        <methodname><replaceable>handler</replaceable></methodname>
+        <type>bool</type><methodname><replaceable>handler</replaceable></methodname>
         <methodparam><type>int</type><parameter>errno</parameter></methodparam>
         <methodparam><type>string</type><parameter>errstr</parameter></methodparam>
         <methodparam choice="opt"><type>string</type><parameter>errfile</parameter></methodparam>
diff --git a/reference/errorfunc/functions/set-exception-handler.xml b/reference/errorfunc/functions/set-exception-handler.xml
index 2f68dbcf74..852bc9a915 100644
--- a/reference/errorfunc/functions/set-exception-handler.xml
+++ b/reference/errorfunc/functions/set-exception-handler.xml
@@ -33,7 +33,13 @@
        This function must be defined before calling
        <function>set_exception_handler</function>. This handler function
        needs to accept one parameter, which will be the exception object that
-       was thrown.
+       was thrown. This is the handler signature:
+      </para>
+      <para>
+       <methodsynopsis>
+        <type>void</type><methodname><replaceable>handler</replaceable></methodname>
+        <methodparam><type>Exception</type><parameter>$ex</parameter></methodparam>
+       </methodsynopsis>
       </para>
       <note>
        <para>
diff --git a/reference/outcontrol/functions/ob-start.xml b/reference/outcontrol/functions/ob-start.xml
index b35da714b4..39d9856c48 100644
--- a/reference/outcontrol/functions/ob-start.xml
+++ b/reference/outcontrol/functions/ob-start.xml
@@ -65,11 +65,32 @@
        return a new output buffer as a result, which will be sent to the
        browser. If the <parameter>output_callback</parameter> is not a
        callable function, this function will return &false;.
+       This is the callback signature:
       </para>
       <para>
-       If the callback function has two parameters, the second parameter is
-       filled with a bit-field consisting of
-       <constant>PHP_OUTPUT_HANDLER_*</constant> constants.
+       <methodsynopsis>
+        <type>bool</type><methodname><replaceable>handler</replaceable></methodname>
+        <methodparam><type>string</type><parameter>buffer</parameter></methodparam>
+        <methodparam choice="opt"><type>int</type><parameter>phase</parameter></methodparam>
+       </methodsynopsis>
+       <variablelist>
+        <varlistentry>
+         <term><parameter>buffer</parameter></term>
+         <listitem>
+          <simpara>
+           Contents of the output buffer.
+          </simpara>
+         </listitem>
+        </varlistentry>
+        <varlistentry>
+         <term><parameter>phase</parameter></term>
+         <listitem>
+          <simpara>
+           Bitmask of <constant>PHP_OUTPUT_HANDLER_*</constant> constants.
+          </simpara>
+         </listitem>
+        </varlistentry>
+       </variablelist>
       </para>
       <para>
        If <parameter>output_callback</parameter> returns &false; original
diff --git a/reference/pcre/functions/preg-replace-callback.xml b/reference/pcre/functions/preg-replace-callback.xml
index 4ecb31dc4b..82106d1dd1 100644
--- a/reference/pcre/functions/preg-replace-callback.xml
+++ b/reference/pcre/functions/preg-replace-callback.xml
@@ -43,7 +43,13 @@
       <para>
        A callback that will be called and passed an array of matched elements
        in the <parameter>subject</parameter> string. The callback should
-       return the replacement string.
+       return the replacement string. This is the callback signature:
+      </para>
+      <para>
+       <methodsynopsis>
+        <type>string</type><methodname><replaceable>handler</replaceable></methodname>
+        <methodparam><type>array</type><parameter>matches</parameter></methodparam>
+       </methodsynopsis>
       </para>
       <para>
        You'll often need the <parameter>callback</parameter> function