protools vs. reason midi problems

[scientifical]

hiya, i'm hoping to find someone who has a solution to a somewhat strange midi problem.
when i have both reason and protools running at the same time, whenever reason is in the foreground with protools in the background, reason stops responding to midi events. if i switch back to pt in the foreground, reason responds to midi. i have plenty of apps i run at the same time (pt, reason, refuse, absynth, reaktor) and reason works fine in the fore or background as long as pt isn't running. i tested absynth and reaktor to see if they had the same problem, and they don't...only reason in the foreground creates this anomoly.

system:
g4 733
reason2
ptle5.0/digi001
oms2.3.8
midiman keystation 49
macos9.2.2

thanks in advance for any light that can be shed on this problem!

-scientific