The mouse is configured twice in the XF86Config file, once for the PS/2 port, and once for the USB port. This is deprecated by the use of /dev/input/mouse stuff by the 2.6 kernel, and should be changed. This duplication leads to, for instance, skipping a page when using the wheel in xpdf.
*** This bug has been marked as a duplicate of 115715 ***
Changed to 'CLOSED' state since 'RESOLVED' has been deprecated.