function overlay_ini( ){	
	var PageInfo=getPageSize();
	//alert(PageInfo[1]+"   "+PageInfo[3]);
	gWidth=PageInfo[2];
	gHeight=PageInfo[3];
	//alert(gHeight);
	//document.getElementById("overlay").style.top = window.innerTop+'px';
	//alert(findPosY("mainscreen"));
	
	if (vBrowser=='FF')	document.getElementById("overlay").style.width = (gWidth-17)+'px';
	else	document.getElementById("overlay").style.width = (gWidth)+'px';
	document.getElementById("overlay").style.width = (gWidth)+'px';
	
	document.getElementById("overlay").style.height = gHeight+'px';
	
	if (vBrowser=='FF')	document.getElementById("overlay").style.top = window.pageYOffset+'px';
	else	document.getElementById("overlay").style.top = document.documentElement.scrollTop+'px';
	
	
	document.getElementById("loading").style.left = parseInt(gWidth/2)-63+'px';
	document.getElementById("loading").style.top = parseInt(gHeight/2)-11+'px';

	//alert(document.getElementById("overlay").style.width);

}

function doShow(obj)
{
	//setTimeout(function(){alert(1);document.getElementById("overlay").style.visibility = 'visible';},3000);
	overlay_ini();
	document.getElementById("overlay").style.visibility = 'visible';
}

function doHide(obj)
{
	//setTimeout(function(){document.getElementById("overlay").style.visibility = 'hidden';},5000);
	document.getElementById("overlay").style.visibility = 'hidden';	
}

function createRequestObject()
{
	//alert("welcome");
	var request_o;
	var browser = navigator.appName;

	if (browser == "Microsoft Internet Explorer")
	{
		request_o = new ActiveXObject("Microsoft.XMLHTTP");
	}
	else
	{
		request_o = new XMLHttpRequest();
	}
	return request_o;

}

var http = createRequestObject();

function showProcessing_msg( msg )
{
	screenHeight = screen.height;
	screenHeightCenter = screen.height/2;
	screenWidth = screen.width;
	screenWidthCenter = screen.width/2;
	document.getElementById('message').innerHTML = "<div id='processing' style='position:absolute;left:0;top:0;margin:0; width:"+(screenWidth-35)+"px; height:"+screenHeightCenter+"px;'><img src='../images/ajax-loader.gif' id='loading-gif'> <h2>Please wait, While Loading...</h2><br /><table align='center'><tr><td id='display_msg'></td></tr></table></div>";
	document.getElementById('display_msg').innerHTML = msg;
}

function hideProcessing()
{
	//document.getElementById('message').innerHTML = "";
	doHide("overlay");
}

/****************************************************/

function load_vendor_exams() {
	//alert("dfkgjfg");
	http.open('POST','includes/ajax/general_functions.php?action=load_vendor_exams');
	http.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
	http.onreadystatechange = update_load_vendor_exams;
	http.send('vid='+document.getElementById('vid').value);
}

function update_load_vendor_exams() {
	if(http.readyState == 4) {
		var response = http.responseText;
		//alert( response );
		//hideProcessing();
		var message = response.split("@@@@");
		
		//alert(message);
		document.getElementById('cert_combo').innerHTML = message[0];
		document.getElementById('exam_combo').innerHTML = message[1];
		<!--document.getElementById('certexam_combo').innerHTML = '<select class="list" name="certexams" id="certexams" size="10" multiple="multiple"><option value="" selected="selected">Select Certification</option></select>';-->
	} else {
		doShow('overlay');
	}
}

function load_cert_exams()
{
	http.open('POST','includes/ajax/general_functions.php?action=load_cert_exams');
	http.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
	http.onreadystatechange = update_load_cert_exams;
	http.send('cid='+document.getElementById('cid').value);
}

function update_load_cert_exams()
{
	if(http.readyState == 4)
	{
		var response = http.responseText;
		//alert( response );
		//hideProcessing();
		var message = response.split("@@@@");
		//document.getElementById('certexam_combo').innerHTML = message[0];
		//document.getElementById('exam_combo').innerHTML = message[1];
		document.getElementById('exam_combo').innerHTML = message[0];
	}
	else
	{
		doShow('overlay');
	}
}