function check_email_registration(siteUrl){
  email=document.getElementById("email").value
  //memberID=document.getElementById("checkmemberID").value
  var url = siteUrl+"include/ajax.asp?search=registration_check_email&email="+email  
  //alert(url)
  if (document.getElementById("div_email_error_message")){
      new Ajax.Updater("div_email_error_message", url,{asynchronous:true, evalScripts:true});
  }   
}