function click_tab(total_tabs,selected_tab) {

	if (document.all && !document.getElementById) {
		document.getElementById = function(id) {
			return document.all[id];
		}
	}


	// make all tabs grey and hide all tables
	for (i=1; i<=total_tabs; i++) {
		x = i.toString();
		idTable = 'table' + x;
		idTab = 'tab' + x;
		document.getElementById(idTable).style.display = "none";
		document.getElementById(idTab).style.background = "url('/About/i/tab_off_edge.gif')";
		document.getElementById(idTab).style.borderBottom = "1px solid #999";
	}

	// highlight selected tab and table
	y = selected_tab.toString();
	idSelectedTable = 'table' + y;
	idSelectedTab = 'tab' + y;
	document.getElementById(idSelectedTable).style.display = "block";
	document.getElementById(idSelectedTab).style.background = "none";
	document.getElementById(idSelectedTab).style.backgroundColor = "#fff";
	document.getElementById(idSelectedTab).style.borderBottom = "1px solid #fff";
}