function createXHR() 
{
	try 
	{ 
		// Firefox, Opera 8.0+, Safari 
		xmlHttp=new XMLHttpRequest(); 
	} 
	catch (e) 
	{ 
		// Internet Explorer 
		try 
		{ 
			xmlHttp=new ActiveXObject("Msxml2.XMLHTTP"); 
		} 
		catch (e) 
		{ 
			try 
			{ 
				xmlHttp=new ActiveXObject("Microsoft.XMLHTTP"); 
			} 
			catch (e) 
			{ 
				alert("Your browser does not support AJAX!"); 
				return false; 
			}
   		}
	}
	return xmlHttp;
}