function onTab(tabID) {
	document.getElementById('tab'+tabID).className = "current tab";
	document.getElementById('tab-content'+tabID).className = "show";
	current_tab = tabID;
}
function offTab(tabID) {
	document.getElementById('tab'+tabID).className = "tab";
	document.getElementById('tab-content'+tabID).className = "";
}
function swapTab(tab) {
	offTab(current_tab);
	onTab(tab);
	return false;
}