by RedSyntax » Fri Feb 27, 2009 7:50 am
Ya, It shouldn't be hard to implement, you just need to write the regexp(I recommend an online regexp checker/assembler) that matches the zip code ranges of your choice.
And also remember it has to go into. The "JavaScript added at start of built-in CheckIt function:" Box found at:
Commerce Setup-->Customize Ordering System-->Shopping Cart Screen