function preload(imgID) {
	if (document.images) {            
		eval(imgID + 'over = new Image()');
		eval(imgID + 'over.src = "http://www.messagehall.com/images/' + imgID + '-on.gif"');

		eval(imgID + 'reg = new Image()');
		eval(imgID + 'reg.src = "http://www.messagehall.com/images/' + imgID + '-off.gif"');
		}
	}

function img_over(imgName) {
	if (document.images) {
		imgOver = eval(imgName + "over.src");
		document[imgName].src = imgOver;
		}
	}

function img_reg(imgName) {
	if (document.images) {
		imgReg = eval(imgName + "reg.src");
		document[imgName].src = imgReg;
		}
	}
	
function pbump() {
	var t=setTimeout("on('resumealert)",1000);
	var u=setTimeout("off('resumealert');",30000);
	}	
	
function toggle(divName) {
	var currentA;

	currentA = (getStyleObject(divName).display == 'none') ? 'block' : 'none';
	getStyleObject(divName).display = currentA;
	}

function off(divName) {
	getStyleObject(divName).display = 'none';
	}
	
function on(divName) {
	getStyleObject(divName).display = 'block';
	}

function getStyleObject(objectId) {
    if(document.getElementById && document.getElementById(objectId)) {
	return document.getElementById(objectId).style;
	} else if (document.all && document.all(objectId)) {
	return document.all(objectId).style;
 	} else if (document.layers && document.layers[objectId]) {
	return document.layers[objectId];
    	} else {
	return false;
    	}
    }

var xmlHttp;
var count = 1;
	
function getExample(cat,vu,depth) { 
	xmlHttp=GetXmlHttpObject();
 
	var url = depth + "/shared/loadstudy.php";
	url = url + "?cat=" + cat;
	url = url + "&vu=" + vu;
	url = url + "&t=" + count;
	count++;
	
	xmlHttp.onreadystatechange = showExample;
	xmlHttp.open("GET",url,true);
	xmlHttp.send(null);
	}
    
function showExample() {
	if (xmlHttp.readyState==4) {
	    if(document.getElementById && document.getElementById("example")) {
			document.getElementById("example").innerHTML = xmlHttp.responseText;
			} else if (document.all && document.all("example")) {
			document.all("example").innerHTML = xmlHttp.responseText;
	 		} else if (document.layers && document.layers["example"]) {
			document.layers["example"].innerHTML = xmlHttp.responseText;
	    	}
	    }
    }

function GetXmlHttpObject() {
	var xmlHttp=null;
	try {
		// Firefox, Opera 8.0+, Safari
		xmlHttp=new XMLHttpRequest();
		}
	catch (e) {
		// Internet Explorer
  		try {
		    xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
		    }
		catch (e) {
			xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
    		}
  		}

	return xmlHttp;
	}