function check_form(theForm){

if (theForm.firstname.value==""){
alert("Please enter your first name");
theForm.firstname.focus();
return false;
}

if (theForm.surname.value==""){
alert("Please enter your surname");
theForm.surname.focus();
return false;
}

var x = theForm.email.value;
var filter  = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
if (filter.test(x) !=true){
alert("Please enter a valid email address");
theForm.email.focus();
return false;
}


if (theForm.telnumber.value==""){
alert("Please enter your telephone number");
theForm.telnumber.focus();
return false;
}


var url = theForm.action;

var propref = theForm.propertyref.value;
var comment = theForm.comment.value;

var message="Website Enquiry\n";
message+="Lead generated: The Serious Business Group (http://seriousgroup.co.uk) \n\n";
message+="Name: "+theForm.firstname.value+"\n";
message+="Email: "+theForm.email.value+"\n";
message+="Telephone: "+theForm.telnumber.value+"\n";
message+="Comments: "+comment+"\n\n\n";

 $.ajax({
   type: "POST",
   url: url,
   data:  { propertyref:propref, message: message },
   dataType: "script"
   });






//reset values
theForm.firstname.value="";
theForm.surname.value="";
theForm.email.value="";
theForm.telnumber.value="";
theForm.comment.value="";


return false;
}