Ranges for scheduling algorithms

Hello,

In older version of Neutrino we had flags like PRIO_FIFO_MAX, PRIO_FIFO_MIN,
PRIO_RR_MAX & PRIO_RR_MIN to set priority ranges for each scheduling
algorithms.
Are we having any such flags in QNX 6.1 also ? If so, why are the priority
ranges (MIN and MAX) specified for each scheduling algorithm ? Is there any
specific reason ? Is there any priority overlap ?
What are those flags .

As i require these informations very urgently please help me in this regard.

Thanks

V S PRAVEEN