stack size (ulimit) problem

Dear all,

I'm using MPB under both cygwin and Mac OS X Leopard. Im unable to use a 
resolution of more than 64 on both OS before I get a stackdump malloc error. Is 
there a way to increase the stack size in cygwin and Mac? 

ulimit -s 32068 doesnt work. Is there a way to specify the stack size to use 
for mpb abd recompile mpb?

Also, I am unable to find mpb-data in my cygwin installation. I followed the 
steps outlined here:
http://www.physics.uc.edu/~thang/mm-cygwin.txt

Lastly, my mac is a duo-core, is it possible to run mpb-mpi on this - would 
this speed things up somewhat?

Many thanks,
Vinod