var xmlHttp12
function availUser()
{ 
var str=document.regform3.username.value;
var home_link=document.regform3.home_link.value;
xmlHttp12=GetXmlHttpObject()
if (xmlHttp12==null)
 {
 alert ("Browser does not support HTTP Request")
 return
 }
 if(str!='')
 {
var url=home_link+"plugins/site/themes/default/availUser.php"
url=url+"?un="+str;
xmlHttp12.onreadystatechange=stateChanged12 
xmlHttp12.open("GET",url,true)
xmlHttp12.send(null)
 }
}
function stateChanged12() 
{ 
if (xmlHttp12.readyState==4 || xmlHttp12.readyState=="complete")
 { 

 document.getElementById("txtUAvail").innerHTML=xmlHttp12.responseText 
 } 
}
function GetXmlHttpObject()
{
var xmlHttp12=null;
try
 {
 // Firefox, Opera 8.0+, Safari
 xmlHttp12=new XMLHttpRequest();
 }
catch (e)
 {
 //Internet Explorer
 try
  {
  xmlHttp12=new ActiveXObject("Msxml2.XMLHTTP");
  }
 catch (e)
  {
  xmlHttp12=new ActiveXObject("Microsoft.XMLHTTP");
  }
 }
return xmlHttp12;
}