function createRequest(){
    var client = null;
    try{
    	client = new XMLHttpRequest();
    }catch(e){
    }
    
    if(client == null){
    	var namePrefixes = ["Msxml3", "Msxml2", "Msxml", "Microsoft"];
    	for(var i = 0; i < namePrefixes.length; i++){
    		var name = namePrefixes[i] + ".XMLHTTP";
    		try{
    			client = new ActiveXObject(name);
    			if(client != null){
    				break;
    			}
    		}catch(e){
    		}
    	}
    }
    return client;
}