var currentRegion = '-1';

function showRegion (id, max) {
	// If previous Region is shown, hide it!
	if (currentRegion != '-1') {
		for (i=1; i<=max; i++) {
			if (document.getElementById) {
				document.getElementById('region_'+i).style.display = 'none';
			} else if (document.all) {
				document.all['region_'+i].style.display = 'none';
			} else {
				alert ('This link does not work in your browser.');
				return;
			}
		}
	}
	// Is id = '-1' ?
	if (id == '-1')
		return;
	// Show new Region
	if (document.getElementById) {
		document.getElementById('region_'+id).style.display = 'block';
	} else if (document.all) {
		document.all['region_'+id].style.display = 'block';
	} else {
		alert ('This link does not work in your browser.');
		return;
	}
	currentRegion = id;
}