Unreal Tournament lost threads under kernel 2.6.2

[Aivils.Stoss at unibanka.lv]

Hi All!

I switch to new distro: Mandrake 10.0-beta2
which have: Xfree 4.4-902mdk

I install Nvidia comercial drivers version 1.0-5336
I install vanilla Linus tree stock kernels 2.4.23 and 2.6.2

I play "UnrealTurnament" under both kernels.
Under 2.6.2 i have "poor performance" feeling - that is not same as fps.

I search possible cause. I have got strange phenomen.
All ut family games ut, ut2003, ut2004demo fork 4 processes under 2.4.23
but use 1 process under 2.6.2.

Is that issue?
Is that Mandrake specific issue?
Is ut forking configurable?
Hide 2.6.2 additional threads?

Aivils Stoss