DELL LCD monitor falls asleep

after sometime and will not wake up until we reboot the system. It is a DELL 24" LCD connected to a sunblade 1500.

my power.conf file is set like this:

# more /etc/power.conf
# Copyright (c) 1996 - 2001 by Sun Microsystems, Inc.
# All rights reserved.
#
#pragma ident "@(#)power.conf 1.16 01/03/19 SMI"
#
# Power Management Configuration File
#
# This entry keeps removable media from being powered down unless the
# console framebuffer and monitor are powered down
# (See removable-media(9P))

device-dependency-property removable-media /dev/fb

autopm default
# Auto-Shutdown Idle(min) Start/Finish(hh:mm) Behavior
autoshutdown 30 9:00 9:00 default
statefile //.CPR

THANKS,

jv