$(document).ready(function() {
    var $btn = $('.form_submit');
    var $form = $btn.parents('.formContainer');

    $form.keypress(function(e) {
        if (e.which == 13 && e.target.type != 'textarea') {
            var $tmpBtn = $(this).find('.form_submit');
            if ($tmpBtn[0].type == 'submit' || $tmpBtn[0].type == 'image' || $tmpBtn[0].type == 'button')
                $tmpBtn[0].click();
            else
                eval($tmpBtn[0].href);
            return false;
        }
    });
});