wxmaxima and ltsp problems



Hello,

im am running wxmaxima on ltsp  (linux terminal server 
project ) at home and at school.

If I am alone, it works fine.
But when (at school) 20 students log in and start  wxmaxima:
- for some it works
- for some of them it is possible to calculate etc, but its 
not possible to plot 
- some get the message "couldn't connect to wxmaxima"
(or similar; sorry, I didn't write down)

If the last ones start maxima (Kde/konsole) they could plot 
in ascii; when I tried the same (alone) the output  was with 
gnuplot  

Any idea, to fix?
which log-file may give more information?

Our System:

- debian 4.0
- kernel 2.6.24-19-xen
- ltsp 5.1.10-1~40.etch.0
- xen on hp proliant
- three virtual servers ; two on the   hp proliant machine; 
one on an other machine
-  Maxima 5.10.0-6
- wxmaxima 0.7.0a-1.1
- gnuplot 4.0.0-5

-- 
mit freundlichen Gr??en
Friedrich Hattendorf

---
Lernen ist wie das Rudern gegen den Strom;
sobald man aufh?rt, treibt man zur?ck
Benjamin Britten