I assume the mouse is working fine in everything apart from openarena?
If it is any help to you I use Debian Lenny amd64, and a Logitech G5 works fine with evdev.
Section "InputDevice"
Identifier "G5 Mouse"
Driver "evdev"
Option "CorePointer"
Option "Name" "Logitech USB Gaming Mouse"
Option "ZAxisMapping" "4 5 6 7"
Option "Emulate3Buttons" "false"
EndSection
I have reversed the tilt buttons with xmodmap.
pointer = 1 2 3 4 5 7 6 8 9 10 11 12 13 14 15 16 17 18 19 20
I have no changes from default mouse settings in openarena's autoexec.cfg, apart from sensitivity.
These pages useful setting up a Logitech G5 and a MX518.
http://www.linux-gamers.net/modules/wiwimod/index.php?page=HOWTO+Mouse+Buttonshttp://adterrasperaspera.com/blog/2006/06/20/logitech-g5-review-under-linux