No I worded that really bad ... what I am trying to say is if you fully are swiching from Marco's USPS and going to USPS J5 (our version ever) ... you need to fix modules.php as Marco's version changed that file originally with references that do not exist if you switch to out USPS version ...

So that might be a clue to the bug you mentioned ...

If that is not what you are doing, switching to the Zen Cart version of USPS, then that is not or may not be 100% of your issue but could be a clue on what is the problem that you are having ...

Does that better explain the tying to that bug and Marco's USPS vs Zen Cart USPS version?