Before blaming mIRC for everything that goes wrong with your script, you should look at your code. "it" can read ($strip(%vars)) perfectly fine, the problem has nothing to do with syntax, but semantics. It's not "reacting" to the strip part because it's not reaching that block of code.
DEBUG your code to ensure that the if statement is getting through. My bet is it's not. Check that the values you're testing in your if condition are actually what you expect them to be, that's likely the issue.
