<!-- Hide script from old browsers

	if (document.images) {
		porta = new Image
		portb = new Image
		
		
		porta.src = "portb.gif"
		portb.src = "portab.gif"
		

	}
	
	function chgImg(imgField,newImg) {
		if (document.images) {
			document[imgField].src= eval(newImg + ".src")
		}
	}
	
	// End hiding script from old browsers -->