gistfile1.js

$('#Form_InterestForm').on('submit', handleSubmit);

var handleSubmit = function(e) {
	var form = $(this),
		data = form.serialize();

	form.find('input').attr('disabled', 'disabled');
	$('#Form_InterestForm_action_doInterestForm').val('Submitting...');

	$.ajax({
		type: "POST",
		url: form.attr('action'),
		data: data,
		success: function(data, textString, jqXHR) {
			form.replaceWith(data);
			$('#Form_InterestForm').on('submit', handleSubmit);
		}
	});
	
	e.preventDefault();
};