Just as a headsup there is a new cleaned up patch here:
http://ck.kolivas.org/patches/SCHED_ISO/2.6.11-rc1-iso-0501192240.diff

The yield bug is still eluding my capture but appears to be related to 
the array switch of yielding and rescheduling as ISO after the fact. 
Still working on it.

Cheers,
Con