I just installed my 2950 in one of our PoPs. I hooked up my 3600 router and it worked fine. My other workstations and servers are also running fine. When I hook up my 5300s the LED lamp on 2950 is GREEN and the sh int command resulted to link and protocol is up. On my 5300s, sh int gave me link is up and protocol is down. I changed the default auto-negotiation process, by manually configuring 5300 and 2950 to use speed 100 and duplex full. But result is the same. Note that when I move the 5300s to HP or Dell it is working fine.