I have a problem with a Network with 4006 layer 2 switches connected via GIG ports to a 6509 layer 3 switch with MSM not a msfc. The application runs very slow over the 4006's if I take a HUB and plug in the devices into the hub traffic runs very fast. If I plug the hub into the 4006 traffic slows to a crawl again. I have found not config problems and seems to only be with this application.