where does gnome store the list of applications associated with files

Hi,
        I want to know where does gnome store its global list of
applications
associated with various file types. The reason for this is that I want
to associate XMMS with mp3 and m3u files for every user on my linux
machine. I do not want to ask every user to do it manually but provide
with some standard applications associated with various files.

Thanks in advance.
VJ