0/0 is not equal to 1. It *should* be an invalid mathematical operation giving a divide by 0 error. mIRC instead just says it equals 0. There was discussion on that in the past, but I don't remember the reasoning behind it. Maybe just to make a script not halt if the denominator is 0.
In any case, you should always check if the denominator = 0, and if so, don't do the math because it's not valid. But whatever way you look at it, 0/0 is never going to be 1.
