CompizFusion problems on ATI ~!

[Radish_Spirit]

when i choose compiz as a windows manager the wallpaper disappears, taskbars go white and everything starts glitching really bad. also borders partly disappear (the ones of the programs that were running before switching to compiz). also screen changes its size (i have a 1400x1050 resolution) so it is like ~1000x1050 (the 400 pixels wide area is dead). but.. compiz and emerald themselves are working fluently.
to get compiz working i followed Wolfden's Sabayon 1.1 PE guide.

I have a sabayon 1.1 PE
graph card is [from lspci] - ATI Technologies Inc Radeon RV250 [Mobility FireGL 9000] (rev 02)
running on dell D600


thanks in advance~!

[EDIT]
Got it working on 1024x768. Can it be a texture size issue?