var xRequest=null
function CreateRequest()
{ 
    try
    {
		xRequest=new XMLHttpRequest();
    }
    catch (trymicrosoft)
    {
	  try
	  {
		xRequest=new ActiveXObject("Msxm12.XMLHTTP")	  	
	  }
	  catch (othermicrosoft)
	  {
		  try
		  {
			xRequest=new ActiveXObject("Microsoft.XMLHTTP")	
		  }
		  catch (failed)
		  {
		    xRequest = null;
		  }
	  }
    }
	if (xRequest==null)
	{
		alert ("Browser does not support HTTP Request")
	}
}