ISA connumdrum on Win2003 Server

I am running ISA 2000 SP2 on a Win2003 Server SP1.  Previously ISA was running on a Win 2000 Server SP4.  We are starting the process of migrating our servers to 2003 and started at the ISA box.  All systems seem to be now working, both inside and outside our private DCHP network.  I am also able to get web access and to use TSAC web connect from outside the network.  In addtion I am able to VPN into the system also.  HOWEVER, the only thing that DOESN'T seem to work is RDC.  I have enabled RDC on the Win2003 server as well as all of the RAS setting in ISA Administrative tools.  I CAN RDC if I use the outside IP of the ISA box.  This is a redirect to my SQL server as that is where my application runs via terminal services.  So I KNOW RDC is enabled and sort of working.  However, I CANNOT use any of the FQDN's of my servers to remotely access them from outside my office.  Inside all is well.  If anyone has encountered a similar issue or has a solution, it would be much appreciated.  Obviuosly, until this is resolved, I cannot remotely manage my servers.  As a side note, RealVNC also will not allow me to connect to any desktop PC's.  So it seems the issue is the tunneling protocol...thanks for any help in advance.

drdickson
IT Manager
CRAB