This package was designed to make Ajax Express Forms work automatically in as many situations as possible.
Luckily it's easy.
If you are you using Magic tabs by @johntheFish read on. Ajax for Express Forms and Magic Tabs work flawlessly together with a simple bit of code. Find a quick explanation in the Magic Tabs Documentation.
You have access to a JS object ajaxForms_express_form that gives you the bID and the AjaxForms object for each form on the page that was ajaxified or supposed to be ajaxified.
Let's say the form with bID 123 is supposed to get the Ajax treatment. But you also have a different script that will interact with the form to put it in a popup or tabs or anything like that.
That lets you determine if the Ajax code was run or not.
If the Ajax code was run first then your script might interfere with it and you might want to rerun the Ajax script after your code has completed.
The script offers you a very handy setForm() function for you to use.
setForm() takes 2 parameters, both optional:
First example: reset all the forms using jQuery
Third Example: reset just 1 form when you know its bID