function doRollover(elem, rollover_color, text_color){
// set background color of TD
	if (elem.parentNode){ // IE5, IE6 and Netscape 6
		if (rollover_color == 'transparent'){   // Netscape does not like the word "transparent".
			elem.parentNode.bgColor = '';    
		}
		else{
			elem.parentNode.bgColor=rollover_color;
		}
	}else if (elem.parentElement && elem.parentElement.setAttribute){ // IE4.
		elem.parentElement.setAttribute("bgColor", rollover_color);
	}else{  // Netscape 4.6x or 4.7x
	//alert("Must be Netscape! do nothing");
	}
	// set color of the link text
	if (elem.children){  // IE4, IE5, IE6 and Netscape 6
		elem.children(0).style.color=text_color;
	}
}