[Cialug] MDK 9.1 won't accept X connection?

[kendall bailey]

I have an old Thinkpad (233Mhz) running Mandrake 9.1.  Recently I added 
a headless P III NetVista to the local network and I'd like to run X 
applications on the NetVista and display on the Thinkpad.  I've done 
this sort of thing many many times, but I can not get the Thinkpad to 
accept a remote X client.  I used "xhost +", and set the DISPLAY on the 
NetVista to the thinkpad:0.0 but all x clients (such as xclock) just 
hang.  Nothing shows up on the thinkpad and no error on the NetVista.  
I've verified with netstat that the thinkpad is listening to port 6000.  
The NetVista will display to any Xvnc server I choose but not the 
Mandrake 9.1 root X server.  What am I missing?

Thanks,
Kendall