R help - Jun 2006 - C stack usage is too close to the limit

I am getting a seg fault and the following error when trying to use an 
embedded version of R in a multithreaded application.

Error: C stack usage is too close to the limit

When I do the same thing in a single threaded app, then there is no problem.
I've tried this with R version 2.3.0, 2.3.1 and even 2.2.1 and the same 
error occurs.

Any tips on how to solve this would be greatly appreciated...