[OGo-XML-RPC] How to tell XMLRPC works?

Hi developers,

I have a slight feeling my OGo doesn't handle xmlrpc calls.
My setup:
- compiled newest sources (07/14/03) on SuSE 7.1 and up and running.
- using the Apache module for 1.3.27
- apache running on port 81 or SSL/443, shouldn't matter
- OGo set up to handle requests on localhost:20000, mapped via 
httpd.conf (as in instructions)
- in the source/build dir, a find for all xmlrpc-related file returns 
this (including some .o file):

[...]/sources/opengroupware.org-sope # find . -iname xmlrpc*
./NGObjWeb/xmlrpc_call.m
./NGObjWeb/NGXmlRpc/XmlRpcMethodCall+WO.h
./NGObjWeb/NGXmlRpc/XmlRpcMethodCall+WO.m
./NGObjWeb/NGXmlRpc/XmlRpcMethodResponse+WO.h
./NGObjWeb/NGXmlRpc/XmlRpcMethodResponse+WO.m
./NGObjWeb/NGXmlRpc/shared_debug_obj/ix86/linux-gnu/gnu-fd-nil/XmlRpcMethodCall+WO.o
./NGObjWeb/NGXmlRpc/shared_debug_obj/ix86/linux-gnu/gnu-fd-nil/XmlRpcMethodResponse+WO.o
./NGObjWeb/shared_debug_obj/ix86/linux-gnu/gnu-fd-nil/xmlrpc_call.o
./NGObjWeb/shared_debug_obj/ix86/linux-gnu/gnu-fd-nil/xmlrpc_call


What I've tested so far:
"xmlrpc_call http://localhost:20000/RPC2"; -> returns HTML source of the 
login page
[...]
"xmlrpc_call http://localhost:81/OpenGroupware/"; -> same with all urls

The error message appended to the html output is always:

Exception caught
Name  : XmlRpcCallFailed
Reason: got malformed XML-RPC response ?!

How can I tell my setup is right to handle xmlrpc calls?
Do I explicitly have to tell OpenGroupware.woa to handle xmlrpc?

thx,
Chris
[ who'd _really_ love to integrate OGo with TYPO3 ;) ]