Finally got DVI out working on my MacBookPro Core2Duo (ATI X1600) with Kubuntu Edgy ! =P . Used this configs to enable “clone” mode. If you want to make “dual-head” mode you’ll need to change somethings..
It’s kind of easy. Just run the following commands and everything will work perfectly:

• sudo aticonfig –desktop-setup=clone
• aticonfig –query-monitor
• sudo aticonfig –enable-monitor=crt2,lvds  – (assuming crt2 is dvi out…)
• sudo aticonfig –mode2=1024×768,800×600,640×480