kms hinders desktop effects

When kernel mode setting is on, desktop effects don’t work.

My system: Centrino laptop, radeon x300 mobility graphics card.
I am using an extern VGA-0 Monitor, switching LVDS off by xrandr script.

Just read somewhere: Radeon driver needs adaption to fully (dri) work with kernel mode setting.

Shall we open a Fate to request to not kms as default for 11.2 as long as this stuff does not work?
Working with a laptop with an external monitor it is not even faster using kms…