Description of problem:
Can't log in to new F7 installation via XDMCP.  Message in /var/log/messages:

      kernel: gdmlogin[3099]: segfault at 00000000000000001c rip
00002aaab617a318 rsp 00007ffffff649410 error 4

I added debugging to log -- this happens right after

      gdm[2501]: Handling user message: 'GET_CONFIG daemon/AddGTkModules hostname:0'
      gdm[2501]: Handling user message: 'CLOSE'

Version-Release number of selected component (if applicable):
gdm-2.18.4-2.fc7.src.rpm

How reproducible:
always happens from Exceed on Windows 

Steps to Reproduce:
1.  Set Exceed for XDMCP Query of F7 machine
2.  Launch it -- silently quits with no connection
3.  See segfault message in F7 log file
  
Actual results:
no connection

Expected results:
Trying to replace an old i386 machine.  It runs FC3 with gdm-2.6.0.5-6 and works
fine with Exceed.

Additional info:
Same results, even if I set remote logins disabled.