direct play of internet radio

Hello guys,
I would like to play an internet radio on my Frodo with a direct command to xbmc through my PC/control system. In Eden I was able to do it via HTTP command like this:

http://IPofMyXBMC/xbmcCmds/xbmcHttp?command=PlayFile(http://217.73.28.42:8000/aligator-128.mp3.m3u)

In Frodo it is not possible as the HTTP commands do not work in general (or am I missing something?).

Please could you help me retrieve my previous functionality?

Many thanks.

Korst