Need to revert vCenter5.1 to vCenter 4.1 snapshot but....

So I successfully upgraded my vCenter Servers and SRM from 5.0.1 to 5.1 BUT I made a rookie mistake and didnt check compatibilty.....There is no RecoverPoint SRA compatible with 5.1 until next month, allegedly November 8th....so no biggie, I can revert to a snapshot for my vcenter servers...

However, I upgraded the vCenter agents on the hosts (v. ESXi 4.1).   Is there a quick and easy way to remove the 5.1 vCenter agent and reinstall the 4.1 agent?  Without downgrading the vCenter agents, I cant connect them to the vCenter 4.1 servers.

Thanks

ShDog