vmware strange scheduling priority

[Peter Enderborg]

Im playing with vmware 4.0 workstation. And it do some strange things.
I start vmware with nice and I got this:
26499 pme       19  19 95980  93M 95020 R N    12 32.6 24.8   8:55 
vmware-vmx
26439 pme       19  19  8416 8008  7692 R N     8  3.2  2.0   2:02 
vmware-vmx
26492 pme        6 -10 95980  93M 95020 R <    12  2.6 24.8   0:34 
vmware-vmx
26409 pme       19  19  4900 3916  2484 S N     0  1.0  1.0   0:29 vmware
26433 pme        5 -10  8416 8008  7692 S <     8  0.5  2.0   0:29 
vmware-vmx
26493 pme        5 -10  8056 7268  6988 S <     0  0.5  1.8   0:20 
vmware-mks
26495 pme        9   0 67672  65M 66888 S       0  0.2 17.4   0:11 
vmware-vmx

It have changed the prioority to -10 for some of its own tasks. How can 
that be done? Its a non suid binary started
by a normal user. It's very ugly, but Im more intressted in how it can 
be done.
The kernel is a 2.4.20.