Vista - Vista RDP to Windows 2008 Server

We have just started adding Windows 2008 servers to our DMZ and it seems
Vista can't RDP to them.

RDP is enabled on the servers.
Connecting to the Win 2k8 servers I get a login prompt that lets me know
"something" is comunicating.

It is using the "less secure method" but nothing changes whe changing to
Network level Authentication.

The Win 2k8 servers are in another domain which trusts ours, I have an
account in the DMZ domain which I provide to the login promp I get, then it
sits there for about 3 to 4 minutes then is says "This computer can not
connect to the remote computer. Try again. If the problem continues, contact
the owner of the remote computer or your network administrator."

I can RDP into any Win 2k3 server in the DMZ domain successfully from my
Vista computer.

Running RDP in administrator mode allowed me to RDP to the Win 2k8 server
exactly ONCE.

Other users on our subnet with Vista can not RDP to the Win 2k8 servers in
the DMZ.

Other users on our subnet with XP CAN RDP to the Win 2k8 servers.

Users with Virtual PC installed on their Vista machine running XP in the
virtual PC CAN RDP to the Win 2k8 servers in the DMZ.

I can RDP into other Win 2k8 servers that are not in our DMZ from my Vista
box.

Disabling the firewall on my Vista box and the Win 2k8 servers changes
nothing.

The Win 2k8 servers are running on VMWare and using Virtual center I can
successfully log into each of the two servers and RDP to the other and get
successfully logged in.

There is a checkpoint firewall that we have to go through to get to the DMZ,
it's rule is to allow any IP from the subnet I'm on to connect to the DMZ
and that rule is working because I can get to all other servers in the DMZ.

I'm not sure what is going on. Any Ideas?

TIA