XtremeBain the client was working fine in 0.27 (apart from that odd crash..), i've been playing it (purely on linux) for a while now...
It is not the most complicated game to run at all, usually you have to do no more than
./paintball2 (or were you referring to the development)
My crash is the exact same as the original posters.
P.S although i have Ubuntu installed I do not use as my main system I am not going to spam the Ubuntu forums, I run arch as my main system (i'm not going to spam arch's either) - it plays paintball faster than any other system i've tried..
And anyway do you not want more users ? (Linux users are more likely to have access to a server....)