var request=false;
var requestId=false;

function getRequest() {
    if(request.readyState!=4) {
        document.getElementById(requestId).innerHTML='<img src="image/loading.gif" alt="Loading Content" />';
    }
    
    else if(request.readyState==4) {
        if(!request.status==200) {
            alert("Fehler:"+request.status); 
        } else {
            document.getElementById(requestId).innerHTML=request.responseText;
        }
    }

}

function makeHandler() {
    if(window.XMLHttpRequest) {
        request=new XMLHttpRequest();
    } else if(window.ActiveXObject) {
        try {
            request=new ActiveXObject("Msxml2.XMLHTTP"); //IE 5
        } catch(e) {
            try {
                request=new ActiveXObject("Microsoft.XMLHTTP"); //IE 6
            } catch(e) {
                
            }
        }
    }
    return request;
}

function ajax(id,module,action,content) {
    request=makeHandler();
    requestId=id;
    if (!request) {
        alert('There was an error while creating the XMLHTTP handler');
        return false;
    } else {
        request.open('get', 'ajax.php?module='+module+'&action='+action+'&category='+content, true);
        request.onreadystatechange=getRequest;
        request.send("");
    }
}