Please apply the following patch on top of 2.5.6x. This patch does the
following:

- repair broken system-wide overflow notification
- repair broken per-process notification
- fix a problem in the resrved bitmask for opcode 
  matcher8,9 for McKinley as reported by UIUC.
- forcing of bit2 for pmc8/pmc9 now part of reserved bitmask
- add the unsecure option to perfmon
- update to perfmon 1.4 (similar to 2.4)