Zencart 1.3.7.1

If you use just "Paypal Express Checkout" and not Payflow Pro and you make the upgrade mentioned here to your existing 1.3.7.1:

http://www.zen-cart.com/forum/showpo...82&postcount=1

Zen Cart v1.3.7.1:
Edit your /includes/modules/payment/paypalwpp.php file and make the above changes at lines 1012-1013.

......are you still okay using zen 1.3.7.1 after Sep 01 ?

OR, must you upgrade to zen 1.3.8 no matter what?

Totally critical, tons of hacks, need to be sure, thanks