Hugs Crashes W2K

[ion]

Hug's crashes when I try to use the 'prime' function
defined below, note that the function calls prime_helper
and this is the likely cause of the crash, also note that
the reason for the crash is probable error in the
function definition. This is on Windows 2000, is there
a fix for this (apart from, "don't use windows" ;))
as otherwise the tool is unusable?

ion

-- Checks whether or not a given Integer is prime
prime:: Integer -> Integer
prime x = if x==0 then error "x = 0" 
          else
             if x<0 then prime (0-(-x))
             else prime_helper x 2 

-- Used within 'prime' to determine if a number is prime or not
prime_helper:: Integer -> Integer -> Integer
prime_helper x y =
   if ((rem) x y)==0 then error "NUMBER IS NOT PRIME"
   else
      if x==y-1 then error "NUMBER IS PRIME"
      else prime_helper x y+1