Comment 14 for bug 206952

same here:

Compaq/hp nc6320
Hardy

/var/log# uname -a
Linux hatchet 2.6.24-16-generic #1 SMP Thu Apr 10 12:47:45 UTC 2008 x86_64 GNU/Linux

Also
/var/log# cat pm-suspend.log
...
/usr/lib/pm-utils/functions: line 143: echo: write error: Resource temporarily unavailable
...

On line 143, there's a test function that checks whether /dev/pmu exists inside line 143:
[ -e /dev/pmu ] && /usr/lib/hal/hal-system-power-pmu sleep || echo -n "mem" > /sys/power/state

The entire function:

do_suspend()
{
        if [ -x /usr/sbin/s2ram ]; then
                if [ -n "$S2RAM_OPTS" ]; then
                        # Trust HAL or the user to pass the correct options
                        /usr/sbin/s2ram $S2RAM_OPTS
                elif /usr/sbin/s2ram --test > /dev/null ; then
                        # Trust s2ram's internal whitelist
                        /usr/sbin/s2ram
                else
                        # Unknown machine
                        echo "This machine is unkown, please try to find out how to suspend this machine. See s2ram(8)."
                fi
        else
                [ -e /dev/pmu ] && /usr/lib/hal/hal-system-power-pmu sleep || echo -n "mem" > /sys/power/state
        fi
}