function emptyvalidation(entered)
{
with (entered)
{
if (value==null || value=="" || value==0)
{return false;}
else {return true;}
}
} 

function emailvalidation(entered)
{
with(entered)
{
// var emailFilter=/^.+@.+\..{2,3}$/;
//alternate email filter (more simple)
var emailFilter=/^([\w-]+(?:\.[\w-]+)*)@((?:[\w-]+\.)*\w[\w-]{0,66})\.([a-z]{2,6}(?:\.[a-z]{2})?)$/i
if (!(emailFilter.test(value))) 
{
	return false;
}
else
{
	return true;
}
}
}

function custServiceForm(entered)
{
var err = 0;
var msg = "Error:\n\nThe following fields are mandatory and are missing or incorrect:-\n\n";
with(entered) {
	if (emptyvalidation(entered.name)==false) {err++; msg+="Name\n";};
	if (emptyvalidation(entered.address)==false) {err++; msg+="Address\n";};
	if (emptyvalidation(entered.telephone)==false) {err++; msg+="Telephone\n";};
	if (emailvalidation(entered.email)==false) {err++; msg+="Email\n";};
	}
if (err!=0) 
{
	alert (msg);
	return false;
}
}