function clsswp(id, cls){
	if (document.getElementById) { // DOM3 = IE5, NS6
		document.getElementById(id).className = cls;
	}
	else {
		if (document.layers) { // Netscape 4
			document.id.className = cls;
		}
		else { // IE 4
			document.all.id.className = cls;
		}
	}
}

function imgswp(id, src) {
	//safe function to hide an element with a specified id
	if (document.getElementById) { // DOM3 = IE5, NS6
		document.getElementById(id).src = src;
	}
	else {
		if (document.layers) { // Netscape 4
			document.id.src = src;
		}
		else { // IE 4
			document.all.id.src = src;
		}
	}
}

function highlight_on(id){
	if(activepage!=id) {
		imgswp("br_" + id, "images/tabs/tab_right_hover.png");
		imgswp("bl_" + id, "images/tabs/tab_left_hover.png");
		clsswp(id, 'tab_hover');
	}
}
function highlight_off(id){
	if(activepage!=id) {
		imgswp("br_" + id, "images/tabs/tab_right_off.png");
		imgswp("bl_" + id, "images/tabs/tab_left_off.png");
		clsswp(id, 'tab_off');
	}
}