Only Display 0 is unlimited

[Frey Dennis F KPWA]

Greetings,
With xorg server 1.1.0  and xdm clients issuing "Xorg -query 192.168.0.1 :X"
after login only X=0 display draws the entire initial screen even if
assigned to a higher number virtual terminal. In our xdm applications
displays 1,2,... all stop drawing just before writing the top menu line
whether a single instance or multiple instances are started and regardless
of virtual terminal assignment. This is true on Intel, ATI and Nvidia
graphics cards on AGP and PCIe busses with Intel and AMD CPUs running Linux
2.6.18.1. Display 0 always works and any higher display is always
shortchanged with plenty of resources unused. There must be a difference in
how display 0 is allocated in Xorg . Any clues on how to fix this?

Thanks
Dennis Frey