Small Wordpress Fix

I have a wordpress install here: [login to view URL] that has a basic email script enabling visitors to send an email to the seller of an item (see here: [login to view URL]). This email script is currently not working and I do not know why. The email script has not been edited at all - it remains exactly as per the Wordpress theme I purchased. Unfortunately the developer of the Wordpress theme does not offer support and so I need to get help from someone else. I have very limited programming experience but I am quite sure that this will be a very quick fix for someone who understands the code. I believe the form is Ajax and have copied the code below. I have also spoken to my hosts (Freehostia) who say that there is no problem their end. Help to resolve this would be greatly appreciated. $j("#contactForm").submit(function(e){ var $valid = false; if ('' == 'true') $valid = check_recaptcha(); else $valid = true; if ($valid == true) { $[login to view URL]({ type : 'POST', url : '', dataType: 'json', cache : false, data : { action : 'dox_send_mail', name: $j("#name").val(), email: $j("#email").val(), phone: '', title: '', message: $j("#message").val(), mailto: $j("#post_id").val() }, success : function(response) { $j(".single-auto-alert").removeClass('alert-success alert-error alert-warning'); $j(".single-auto-alert").addClass([login to view URL]); $j(".single-auto-alert p").empty(); $j(".single-auto-alert p").append([login to view URL]); if ([login to view URL] == "alert-success") { $j("#name").val(""); $j("#email").val(""); $j("#message").val(""); } create_recaptcha(); $j('.single-auto-alert').css('display','block'); $j('.single-auto-alert').delay(4000).slideUp(350); } }); }