function hideMain(el) {
	for (i = 0; i < el.childNodes.length; ++i) {
		if (document.getElementById && document.getElementById('maincontent') && el.childNodes[i].nodeName == 'UL') {
			document.getElementById('maincontent').style.visibility = 'hidden';
			break;
		}
	}
}

function showMain() {
	if (document.getElementById && document.getElementById('maincontent'))
		document.getElementById('maincontent').style.visibility = 'visible';
}