The only attempt that I know of requires the WASP SOAP stack but it should give you an idea of how write your own extensions.  AFAIK, the extensions are written specifically for SAXON.  Here's a link to the demo:
-----Original Message-----
From: []
Sent: Thu 11/7/2002 4:58 AM
Subject: [saxon] Is there any xslt-extension for SOAP-RPC?

Does anyone know if there is any implementation of (or study for) XSLT
extension elements (most preferably for Saxon) which enables your XSL
stylesheets to invoke SOAP RPC to obtain arbitrary Web Service results?

The idea is similart to saxon-sql extension elements. As the sql-extension
is possible, then SOAP-RPC-extension should also be possible provided with
some SOAP engine (such as Apache Axis1.0). Has anyone already developped
it? ---then, I would like to use it.

If you know any resources (web articles etc..) for me to refer, please let
me know.

Thank you in advance.

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