help with X for dual head

[Diego Enrique Rodriguez <derodriguez@uvirtual.ean.edu.co>]

Hi lists,
I have a compaq laptop armada v300 with debian sarge, and I'm wanted to work with dual head and Xinerama.
The configuration of XFree is perfect with Xinerama but I don't know why is not funtionality?

my XF86Config-4 see in http://uvirtual.ean.edu.co/~derodriguez/XF86Config-4 

any idea

bye
Diego E. Rodriguez D.
Bogota Colombia