The logitech drivers will not load on Windows 2003 and the included drivers do not support the middle button.
However, there is a solution. The 9.791 build 25 and the brand new 9.80 drivers from here:
http://www.logitech.com/pub/techsupp...e/mw980enu.exe
do work if you install them in XP compatibilty mode.
I HAVE tested the 9.80 ones.