We recently added a 2851 router to our network. It connects to a 3750 switch via a MOE circuit. The link is up just fine (interface up, line protocol up), we can ping or telnet to anywhere in our network from the 2851, but we cannot pass any higher level application traffic (web, Outlook, DICOM, etc) from the 2851 "side" of the network over the link. I do not detect any types of errors. Note that a VPN is not being utilized.