Hi. I have a WS-C6509-E running 12.2(33)SXH4, and the following modules:

1   48  CEF720 48 port 10/100/1000mb Ethernet  WS-X6748-GE-TX     XXX

2   48  CEF720 48 port 10/100/1000mb Ethernet  WS-X6748-GE-TX     XXX

3    6  Firewall Module                        WS-SVC-FWM-1       XXX
5    5  Supervisor Engine 720 10GE (Active)    VS-S720-10G        XXX

Last night, I inserted a new WS-X6748-GE-TX into slot 7. Immediately after I had secured the ejector levers, the switch spat pages upon pages of unintelligible error messages in the console, and the two cards already present powered off by themselves. The switch itself didn't crash, so I removed the new card, powered cards 1 and 2 back on from the terminal, and observed all the links go up. However, there was no traffic and my network was still down without a clear reason. As a panic move, I reloaded the entire switch, and as the FWSM booted, I noticed the following peculiar error messages right after passing diagnostics:

Apr 14 19:29:59.612: %EC-SP-5-CANNOT_BUNDLE2: Gi3/1 is not compatible with Po307 and will be suspended (vlan mask is different)
Apr 14 19:29:59.616: %EC-SP-5-CANNOT_BUNDLE2: Gi3/2 is not compatible with Po307 and will be suspended (vlan mask is different)
Apr 14 19:29:59.916: %EC-SP-5-CANNOT_BUNDLE2: Gi3/3 is not compatible with Po307 and will be suspended (vlan mask is different)
Apr 14 19:29:59.920: %EC-SP-5-CANNOT_BUNDLE2: Gi3/4 is not compatible with Po307 and will be suspended (vlan mask is different)
Apr 14 19:29:59.920: %EC-SP-5-CANNOT_BUNDLE2: Gi3/5 is not compatible with Po307 and will be suspended (vlan mask is different)
Apr 14 19:30:01.211: %EC-SP-5-CANNOT_BUNDLE2: Gi3/6 is not compatible with Po307 and will be suspended (vlan mask is different)

After scratching my head for a bit and reloading just the FWSM, the etherchannel came up and everything was back to normal. I'm stumped as to what happened. It seems obvious that there's a hardware or firmware problem with the new card, but how can the internal etherchannel fail with messages like the above? I have not customized it at all. Did something crazy happen to the VLAN database when I installed the faulty card, and why did reloading the FWSM help? Have I missed something obvious in the release notes? Is there anything I can do as a precaution to prevent this from happening in the future? Any input is greatly appreciated. Thanks.