Error in starting graphics monitor with openwindow version 3

I am getting the following error when I tried to run the grass4.0
under openwindows version 3. Any ideas? I never had problem with openwindow
version 2.

d.mon start=x2
Graph_SetX: display :0.0 doesn't know font 9x15
Please start graphics monitor <x2>.

Srinivasan.
srin@brcsun1.tamu.edu