exception outside of stack limits

[Robert Lunnon]

There is a warning in signal_i368.c 

WARN( "exception outside of stack limits in thread %04lx eip %08lx esp %08lx 
stack %p-%p\n",
                   GetCurrentThreadId(), EIP_sig(sigcontext),


Can anyone tell me what this "means" in terms of what would have to go wrong 
to generate this warning ??