mercator return codes

[murky]

In a UNIX script that calls mercator 5.1 we get different return codes on different unix hp machines. On one machine we get zero return code ok but on the other we get strange return codes include 64, 96, 112, even though map worked ok. I'd just like to test in the script whether the map worked. Any ideas what could be causing this difference? and why these codes are not in the documentation which only mentions 0 to 31.