Grass4 d.mon problem under Debian 2.1

[Adalberto da Silva]

Hello, Grass users!

I'm trying to run Grass4.2.1 (version 21, Markus' binaries) but d.mon
reffuses to work properly.
When I try to open a display, for instance 'x0', the program freezes. When I
try to interrupt with CTRL+C, I get the message:

"Problem selecting x0. Will try once more"

and it remains frozen. Another CTRL+C kills it.
When I browse the locks directory, there's a file lock created.
I'm using Debian 2.1, a libc.so.6 release, and it's fine with Grass 5. D.mon
in this version is O.K. and brings me the message:

"got a True Color (Read-Only) Visual
Graphics driver [x0] started"

I tried to run X with a lower color depth (8 and 16) but Grass4 d.mon still
reffused to work.
Is there any clue?
Many thanks,

Adalberto da Silva