var NS6 = false;
var IE4 = (document.all)? true:false
var NS4 = (document.layers)? true:false
var NS6 = (document.getElementById)? true:false

function rollover(button,axtn){
	if (document.images){ document.images[button].src="graphics/"+button+axtn+".gif";	}
}

function popup(newurl,winWidth,winHeight,tb){

	mw = 640;
	mh = 480;
	
	if (NS4) {
   		mw = screen.availWidth;
   		mh = screen.availHeight;
	}
	
	if (IE4||NS6) {
		mw = screen.width;
   		mh = screen.height;
	}
	
	mw = mw - 100;
	mh = mh - 100;
	
	scr = "no";
	
	if (winWidth>mw){
		scr = "yes";
		winWidth = mw;
		}
		
	if (winHeight>mh){
		scr = "yes";
		winHeight = mh;
		}
	
	starttext = "toolbar=no,location=no,directories=no,status=no,scrollbars=" + scr + ",resizeable=no,";
	if(tb=="print") starttext = "toolbar=yes,location=no,directories=no,status=no,scrollbars=yes,resizeable=no,";
	featuretext = starttext + "width="+winWidth+",height="+winHeight+",left=5,top=5";
	mainView = window.open(newurl,'ImagePreview',featuretext);
	mainView.focus();
}