diff --git a/language/operators.xml b/language/operators.xml
index 3f96b30992..6e46210e44 100644
--- a/language/operators.xml
+++ b/language/operators.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="iso-8859-1"?>
-<!-- $Revision: 1.138 $ -->
+<!-- $Revision: 1.139 $ -->
  <chapter xml:id="language.operators" xmlns="http://docbook.org/ns/docbook">
   <title>Operators</title>
   <simpara>
@@ -952,10 +952,22 @@ Expression: 0 = -4 << 62
    </para>
    <warning>
     <para>
-     Don't right shift for more than 32 bits on 32 bits systems. Don't left shift
-     in case it results to number longer than 32 bits.
+     Don't right shift for more than 32 bits on 32 bits systems.
+     Don't left shift in case it results to number longer than 32 bits.
+     Use functions from the gmp extension for bitwise manipulation on
+     numbers beyond PHP_INT_MAX.
     </para>
    </warning>
+   <para>
+    See also
+    <function>pack</function>,
+    <function>unpack</function>,
+    <function>gmp_add</function>,
+    <function>gmp_or</function>,
+    <function>gmp_xor</function>,
+    <function>gmp_testbit</function>,
+    <function>gmp_clrbit</function>
+   </para>
   </sect1>
 
   <sect1 xml:id="language.operators.comparison">