I have a WiSM installed in slot 4 of a 6509 chassis. Every once in a while I see Gi 4/9 going down/up. The logs indicate that it did so within the same second, so I'm wondering if it really ever went down at all. 'show wism status' all say oper-up, and I don't see any impact to users. Knowing that the WiSM uses many physical connections to the backplane as one logical connection, I suspect what's going on could be physical or software related. We're running 220.127.116.11 on them.