XFree: LCD and CRT simultaneously

[Olaf Stetzer <olaf.stetzer@gmx.net>]

Hello list,

I just received a port replicator for my Notebook, so
I can use a normal mouse/keyboard and monitor in my
Office. It all works fine (having both displays at the same
time) but the timing (videomode) for the external CRT 
seems to be bad.
Now I am not sure how to configure XFree to have a good
display on screen (high refresh rate) and also be able to
use the LCD. Are there two sections in XF86Config-4 for
the two outputs or is the setting done by 
dpkg-reconfigure xserver-xfree86 
only valid for CRT (modelines) and LCD works just fine 
with every setting?

Thanks for your help,

Olaf 

Specs: ati rage LT pro, Xfree 4.1 (sid), kernel 2.4.17
-- 
"Jazz is not dead, it just smells funny!" Frank Zappa