[8notime]

For what it's worth I've heard that this doesn't work on any of the TP2's, so I don't think it's unique to Verizon.

Have you played around with the Select Networks option in the Advanced Connections settings. There's an option to choose which network is used for private networks vs. public networks. Once the VPN is up, if the RDP is connecting to a private IP address, that might force it to go through the PPTP tunnel based on how you've set the private network settings. I use a different VPN otherwise I'd test this myself. But like I said, I talked to someone the other day that say they couldn't get this to work at all on any TP2.