Author LandAjob
client: WINXP
ssh tunneling through port 5901 (putty) + realvnc viewer localhost:1 or 127.0.0.1:5901
server: Debian Sarge
sshd + vncserver package
please refer to "用Xmanager远程登录Debian主机"
here I modified this method.
Other guys recommended NXserver, IMHO, that's crap.