You might want to try vnc (virtual network computing) from
http://www.realvnc.com .
I'm not sure what you're trying to do, but I usually run the "xserver" on a unix machine to open up an xsession and then use the client to connect from either unix or windows machines. The good thing is that when you disconnect the client, your session is still running, unlike true xwindow forwarding. You can also tunnel it over ssh if need by and also run the "server" on a windows machine, but I've never done the latter.