xf86-video-intel component output not working

[Martin Forget]

we are testing with the git version of the xf86-video-intel driver on  
intel GMA950 chipsets (on a945 i945GTt-VFA
  board from Aopen)

we are experiencing issues with component output (through the break- 
out cable )

setting the TV_MODE with xrandr1.2 works for 720p and 1080i works,
(we still have the choice of xorg resolution)

having a resolution < 1024x768 works,

but trying to use 1280x720 resolution on a 720p output does not work.
same for 1920x540 on the 1080i output.

actually, any resolution higher than 1024x768 does not work on the TV  
output.

this does not seem to be a hardware or bios limitation as the same  
function works perfectly on windows.

the actual symtom is that we see the right most 1/3 of the image on  
the left most 1/3 of the screen  and the rest is black.
sounds like a monitor frequency issue.

does anyone has a suggestion?