Add warning that xpath() doesn't work with non-UTF8 data.

diff --git a/doc/src/sgml/datatype.sgml b/doc/src/sgml/datatype.sgml
index c944d8f5c419c57f2fa29d58912f516f31a0e192..4f64e054fb37a3f9088f297b9fdc48d72cfb5357 100644 (file)
--- a/doc/src/sgml/datatype.sgml
+++ b/doc/src/sgml/datatype.sgml
@@ -3958,6 +3958,14 @@ SET xmloption TO { DOCUMENT | CONTENT };
     processed in UTF-8, computations will be most efficient if the
     server encoding is also UTF-8.
    </para>
+
+   <caution>
+    <para>
+     Some XML-related functions may not work at all on non-ASCII data
+     when the server encoding is not UTF-8.  This is known to be an
+     issue for <function>xpath()</> in particular.
+    </para>
+   </caution>
    </sect2>
 
    <sect2>