Ubuntu - Play RM format movies

When I tried to play the rmvb format movies the first, the totem player said that the "Realvideo 4.0 decode can not be found", so there was only audio but no video. After I searched the internet about that, I found this site: medibuntu.org which has what I need.
The following shows the step to make my Ubuntu 7.10 pc play the rm movie:
1) Install the mplayer (Add/Remove --> Sound & Video --> check the MPlayer Movie Player)
2) Install w32codecs & libdvdcss2

a) sudo wget http://www.medibuntu.org/sources.list.d/gutsy.list -O /etc/apt/sources.list.d/medibuntu.list
b) wget -q http://packages.medibuntu.org/medibuntu-key.gpg -O- | sudo apt-key add - && sudo apt-get update
c) sudo apt-get install w32codecs libdvdcss2

3) Now you can remove the default totem movie player if you like:
Open the Synaptic Package Manager, uncheck the totem-gstreamer (totem, totem-mozilla) and press Apply button
That's all!