Comment 17 for bug 23497

Jon,

That used to fix the problem for me in Edgy with my HP Compaq nw8440, so it's possible that you're seeing the same issue now. Try running the following two commands after waking back up:

  sudo sh -c 'echo -n "i8042" > /sys/bus/platform/drivers/i8042/unbind'
  sudo sh -c 'echo -n "i8042" > /sys/bus/platform/drivers/i8042/bind'

Obviously if you've got no keyboard you'll need to this via ssh or plug in an external USB keyboard.

If that helps, then the fix listed above would work to resolve the problem you're seeing with your Dell, too, so I'd snag the suspend and resume scripts from the patch until they make it into acpi-support proper.