diff --git a/appendices/migration4.xml b/appendices/migration4.xml
index 8c9e4d2f54..857ace33d8 100644
--- a/appendices/migration4.xml
+++ b/appendices/migration4.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="iso-8859-1"?>
-<!-- $Revision: 1.24 $ -->
+<!-- $Revision: 1.25 $ -->
  <appendix id="migration4">
   <title>Migrating from PHP 3 to PHP 4</title>
 	
@@ -215,6 +215,16 @@ php_admin_flag [PHP directive name] [On|Off]
      <literal>error_reporting= E_ALL &amp; ~ ( E_NOTICE | E_WARNING
      )</literal>.
     </para>
+    <warning>
+     <para>
+      When upgrading code or servers from PHP 3 to PHP 4 you should
+      check these settings and calls to
+      <function>error_reporting</function> or you might disable
+      reporting the new error types, especially E_COMPILE_ERROR. This
+      may lead to empty documents without any feedback of what happened
+      or where to look for the problem.
+     </para>
+    </warning>
     <warning>
      <para>
       Using the old values 7 and 15 for setting up error reporting is