Symptom:
6500 VSS with a MEC configuration to multiple downstream switches. 

6500 VSS with Sup2T is not negotiating DTP correctly after doing a redundancy force-switchover. After doing a force-switchover, the member in the port-channel that is now on the standby switch will not proceed to come up until the hello timer of 30 seconds expires from the previous negotiation before the switchover occurs.

Normal set up before the failover works fine. Only is seen when issue the command redundancy force-switchover.

Conditions:
6500 VSS Sup2T MEC configuration 

Port configuration can be standard. This is only seen when using DTP mode dynamic desirable to negotiate the trunking status.