I was using an input mask plug-in on the form as well, which I found was causing the creditcard validator to fail (due to the spaces in the mask between the (4) character groups).
This was fixed by moving line: 1017 to just above line: 1011 which tests for only characters [^0-9-]. This could also have been fixed by adding a space to the regular expression but since the replacement line is already in the code, just moving it accomplishes what we're after.