I use this on my 6700. very good app IMO and many configurable options. in particular I use scaling/server side: 1/2 and update asap turned on and it runs like a champ! theres a new version out but I'm too chicken to try it (if it aint broke...)
I've been using 1.0.1.16 for years now (used it on wm2003se as well). just make sure u have .NET installed.
http://dotnetvnc.sourceforge.net/
hth,
ps tell us if it works on Mogul (it should, that's why I posted)
pps I also forgot to say on my server I'm running Ultr@vnc , scaling might not working with other vnc programs (i remember it crashing if scaling was selected with normal vnc server app)