Need help on XPath to parse some string from XML (for vdr-plex.bundle)

Hi everybody,

I am after a while (2 years) working a bit on the livetv.bundle for VDR. And one thing I wanted to try is to access more information and pictures via a restful API that can be installed into vdr.

Here is my issue now - I can with an online tool or Xmplify access the right node and get a string, but it doesn't seem to work in the init.py code.

Code:

                try:
                artPath = currentEpg.xpath('//epg:param[@name="additional_media"]/poster/@path', namespaces=NAMESPACEEPG)[0]
                Log ("Art %s" % artPath)

While the xml is here http://pastebin.com/bPttVUDF

What am I doing wrong in the python code ? Any kind of help is highly appreciated :-) I basically want to access the pictures, the actors, etc and see what I can do to enrich the info presented in the channel.

Kind regards & thanks a lot,
Alex