Running xubuntu 11.04 64-bit, vendetta 1.8.204

1) Launch vendetta
2) Log-in screen appears
3) Change the default video settings (800x600 => 1920x1080)
4) Click OK
5) Game restarts
6) Video settings look good now
7) Click QUIT
8) Segmentation fault, video setting not saved

strace output after attaching to process in step #6: http://pastebin.com/svj0HHW8

Ok, I think we found the problem and a fix is forthcoming.

In the meantime, you can edit the config.ini to set your resolution to 1920x1080.