function checkMail(email)
{
	var x = email;
	var filter  = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
	if (filter.test(x))
	{
		 return true;
	}
	else 
	{
	  alert('Invalid Email Address')
	  return false;
	}
}