This is what I was able to get from Cisco's error decoder, maybe it can be of some help to you.......
1. %PA-2-UNDEFPABRIDGE: Unsupported Port Adaptor Bridge [hex] in bay [dec]
The PCI bridge on the midplane is broken.
Recommended Action: Ensure that your hardware configuration is supported by your Cisco IOS software. Try to reseat the port adapters. If the problem persists, replace the midplane.
Related documents: No specific documents apply to this error message.