openStack Initialization Issues

[Arthur Urban]

Is there a way I can detect when my main stack receives the openStack 
message versus when my substacks receives the message and pass it all 
the way down to the mainstack? I do once only initialization in my 
mainstack, and I can't seem to reliably detect when a substack is 
triggering the openStack message and skip over the init code. I've tried 
using the target and the me function, nothing seems to work. Too bad 
there is no openMainStack handler. (even using on startUp doesn't help 
me) Ugh...what am i missing? thanx!