Playing Real Video files on Matrix TV

[dctam2004]

Just bought a TBS2910 V2.3 and am running the stock firmware. For now I am just planning to use it as a media player but ran into a problem - some of the video files I play are in real video format (.rm, .rvmb) but XBMC doesn't play them. I guess I am missing the correct codec. Can someone please tell me what I need to do?

Thanks.