I have one OS2 server and 3 OS2 w/s directly connected to a single switch. The devices can communicate via layer 2 on a 1900 switch as well as a 5500 switch. However I am trying to connect them to a 3560 or a 3745. On the IOS based switches they do not communicate locally. There is no IP whatsoever, and they are all on the same VLAN. Any idea on what causes this?