[CentOS] CentOS5 on Dell Latitude D620, Docking Station & Dual Monitors???

I've got a Dell Latitude D620, dell docking station and a Dell 2007WFP
(20" widescreen lcd).  With XP I had the laptop screen and the lcd
working as dual screens.  But for the life of me I cannot get CentOS5
to work with dual screens.  Anyone have this working?  I would greatly
appreciate any assistance.

-matt