No "submission success" message

As of the 1.6.3.3.2 update, all of my forms that are using AJAX do not show the "submission success" message. The form successfully submits, but on the end-users screen, the form just stays put and appears to not submit. This results in multiple submissions and confused users.

To fix the issue, all i have to do is turn off AJAX where the form is being displayed. But, I use a WordPress Multisite setup, and it would take a very long time to run through everyone's sub-sites and make sure they are not using AJAX. Is there a another way to fix this issue?
I have tested this on multiple browsers, and it's been reported to me from other users on different networks

Kevin,
Thank you for getting back to me. I spoke too soon, sorry about that. It looks like my issue was caused by a JavaScript error from another plugin. It's a strange one, as it only shows intermittently. But, the error is not with Gravity Forms. When I find out more about what is the real issue, I will post it here so others can see the fix.

I am experiencing the same error - when a user submits info, there is not a "Success" message:
http://vacationparadiseonline.com/myrtle-beach-gift-package-checkout/

I realize there is an error in line 139, but how do I resolve this?

Thanks!

Good day. I have the exact same issue and I understand it maybe javascript. Would highly appreciate if you can give the direction to fixing this. I have almost disabled all other plugnins to check if the success message appears, but it did not resolve the issue. I have created a test page for you to check:
http://vitizo.com/form-test-ajax/

Thank you! The issue is resolved after updating the jquery files.
Cheers.