Recently for a project I completed I was using jQuery with a form name selector:
$('form[name=form-name]')
I was capturing this form's submit action and creating an AJAX request, etc. Worked great In Firefox, Chrome, even IE8 and IE9.
IE7 and IE6 don't support the form name selector. My solution was to request the form using the div wrapper:
$('div#my-id form')
Before you all ask "Why didn't you just put an ID on the form?" There was a reason. But I don't remember what it was.