Mouse scroll wheel abruptly stopped working

[Temlakos]

What could have caused my mouse scroll wheel to cease to function? It 
was working fine until I had to do a restart to get past a system hang. 
Now the system won't respond to the scroll wheel. And a total system 
shutdown and restart won't solve the problem, either.

I am using Fedora Core 6 on a Gateway 1000XL using the original mouse 
that shipped with the system.

Temlakos