[dev] Horde RPC interface

[Blue Bird]

I've been trying to read and write on calendars from Horde (Kronolith) via RPC
for some time now. I'm using the following example: 
http://wiki.horde.org/WSDLHowTo

The problem is, that I don't get any response from the server (I've tried 2 
completely different servers, where I have an account).

I always get a blank 
answer no matter which method I choose (eg. horde_listAPIs or calendar_list,
which are both listed in the rpc.php?wsdl file).

It looks like I can connect 
successfully to both (if I give wrong username and/or password, I get a login
error).

I couldn't connect to the demo server on the Horde homepage
(http://demo.horde.org/).

Does anyone have a working example for a RPC Horde connection?