Arg, resolution problems on laptop/monitor

[Christopher J. Bottaro]

Hello,
A while ago, I posted a question on to setup my FC3 install to detect if my
laptop is plugged into a monitor and if so, use a certain
resolution/modeline and if not, use another.  Someone suggested that I have
both resolutions and modelines in my xorg.conf and simply use ctrl-alt-+
(or ctrl-shift-+ or whatever the combo is) to change resolutions based on
if I'm using the monitor or not.  Well that didn't work for me.  The key
combo doesn't do anything.

Any ideas?  Thanks!