[Hugs-users] How to increase control stack size

Hello, I'm trying to increase hugs stack limit. Up to certain amount, I was successful with editing prelude.h file, namely modifying constants NUM_STACK and MAX_EVAL_DEPTH. But it seems that effective maximum on the MAX_EVAL_DEPTH is 58161 no matter how large the NUM_STACK is. (Always compiling large model, of course.) How can I increase this limit up to 32MB? What else should I modify to enable evaluation of extremely memory consuming programs? Thanks for any help, Dusan