Password Change Issue

I have a 3 site W2K AD domain setup running T1 lines between them. None of the Windows 98 users can change their passwords regardless of location. They can log into the network fine and are prompted for a password change but then they get the “No Domain Controller” box and only the Windows PWD gets changed.

The users can access shares on the 3 servers as well as Exchange 2000 on the main server. DNS is setup and workstations can PING all three DC’s.

Thoughts?