var request = null;

function createRequest()
{
	try
	{
		request = new XMLHttpRequest()	
	}
	catch(trymicrosoft)
	{
		try
		{
			request = new ActiveXObject("Msxml2.XMLHTTP");
		}
		catch(othermicrosoft)
		{
			try
			{
				request = new ActiveXObject("Microsoft.XMLHTTP");
			}
			catch(failed)
			{
				request = null;	
			}
		}
	}
	if(request == null)
		alert("Error creating request object");
}