diff --git a/functions/domxml.xml b/functions/domxml.xml
index dc0f7a008b..97f5b0b15c 100644
--- a/functions/domxml.xml
+++ b/functions/domxml.xml
@@ -6,7 +6,8 @@
    <simpara>
     These functions are only available if PHP was configured with
     <option role="configure">--with-dom=[DIR]</option>, using the
-    GNOME xml library. These functions have been added in PHP4.
+    GNOME xml library. You will need at least libxml-2.0.0 (the beta
+    version will not work). These functions have been added in PHP4.
    </simpara>
    <simpara>
     This module defines the following constants: