function checkLogin(username, pw) {
	initServerUrl();
	var un = document.getElementById('username').value;
	var pw = document.getElementById('pw').value;
	var url= serverUrl + "ajax/?act=checkLogin&un="+un+"&pw="+pw.replace("#", "%23");
	httpRequest("GET",uncache(url),true,handleResponseLogin);
	return false;
}


//event handlers for XMLHttpRequest

function handleResponseLogin(){

    var xmlReturnVal;
    var jsonReturnVal;

    if(request.readyState == 4){
        if(request.status == 200){

			jsonReturnVal = request.responseText;			
			var result = eval("(" +  jsonReturnVal + ")");
			// JSON lib gives error in Firefox, check later...
			//var reply = jsonReturnVal.parseJSON(); 
			if (result.isAuth) {
				document.getElementById("loginForm").submit();
			} else {
				document.getElementById("loginInfo").style.display="block";
				
			}
			
        } else {
            alert("Sorry, diese Funktion (checkLogin) kann z.Zt. nicht ausgeführt werden.");
        }
    } //end outer if
    
}