var xmlHttp

function signUp(email)
{
   document.newsletter.email.disabled = true;
   document.newsletter.subscribe.disabled = true;
   
   if (email.length==0)
   { 
      document.getElementById( "message" ).innerHTML = "&nbsp;<strong>( Required )</strong>";
      document.newsletter.email.disabled = false;
      document.newsletter.subscribe.disabled = false;
      return;
   }
   
   document.getElementById( "message" ).innerHTML = "&nbsp;<strong>( Please Wait ... )</strong>";
   
   xmlHttp=GetXmlHttpObject()
   
   if (xmlHttp==null)
   {
      alert ( "Your browser does not support AJAX!" );
      return;
   } 
   
   var url="common/newsletter.php";
   url=url+"?email="+email;
   url=url+"&sid="+Math.random();
   
   xmlHttp.onreadystatechange=stateChanged;
   xmlHttp.open("GET",url,true);
   xmlHttp.send(null);
} 

function stateChanged() 
{ 
   if (xmlHttp.readyState==4)
   { 
      if( xmlHttp.responseText == "success" )
      {
         document.getElementById( "finalmessage" ).innerHTML = "<em>Thank you for your interest, you have been successfully signed up to receive the Karen Kataline email newsletter.</em>";
      }
      else
      {
         document.getElementById( "message" ).innerHTML = "&nbsp;<strong>( Invalid )</strong>";
         document.newsletter.email.disabled = false;
         document.newsletter.subscribe.disabled = false;
      }
   }
}

function GetXmlHttpObject()
{
   var xmlHttp=null;
   
   try
   {
      // Firefox, Opera 8.0+, Safari
      xmlHttp=new XMLHttpRequest();
   }
   catch (e)
   {
      // Internet Explorer
      try
      {
         xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
      }
      catch (e)
      {
         xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
      }
   }
   
   return xmlHttp;
}