Setup XBian for webm files

[Michael47]

Hi
First thanks for your work . I add to my HomeNetwork (PC Opensuse 12.3 ( XBMC 12.2), Lenovo Storagecenter Ix4-300d 12TB (with Mysql Server), TV Sony Bravia (HDMI port 2 TV) + Sony Homecinema) my raspberry model B with Xbian.1.02 Beta 2 (with Raspberry Codecs).
And it's work "out of the box". Great
Also the remote control with android Samsung S4 works fine ( after installation HTTP Server + config changes) !!

Now my question:
I have some *.webm files in my mediatheque, I can read this files with the Opensuse 12.3 Box, but with the Raspberry Xbian i've only the sound on the Sony TV.
After Google search i install the deb ffmpeg packages, same issue. What must I do for setup webm files in my Raspberry Xbian Box.

Merci par avance

Michael