Using Converter 3.0.1 with VC 2.0.2 and ESX 3.0.2, we can't access the VC server because it thinks it is an ESX 2.x host and won't let us connect to VC. We can connect fine to the ESX hosts as a destination.
We did have to change the default web port to something other than 80 during the VC install. Could that be causing it to think it is a 2.X ESX host and not VC?