function signUp() {

  user_email = jQuery('#signupemail').attr('value');

  // validate email addrses
  var emailRegEx = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
  if (!user_email.match(emailRegEx)) {
    //    jQuery('error_msg').innerHTML = "<br>Please enter a valid email address";
    alert("Please enter a valid email address");
    return;
  }

  jQuery.ajax({
    type: "GET",
        url: "/wp-content/themes/alaska/ajax.php",
        data: 'email=' + user_email,
	success: function(msg){
  	  jQuery('#signupemail').attr('value', msg);
      }
    });
}