var lastRegionIndex = -1;

function updateRegion() {
	var regionList = document.getElementById('regionList');		
	var provinceList = document.getElementById('provinceList');
	
	if (provinceList.value != 1) {
		lastRegionIndex = regionList.selectedIndex;
		
		var elOptNew = document.createElement('option');
		elOptNew.text = 'Région non nécessaire';
		elOptNew.value = '0';			
		
		if (!document.all) {
			regionList.add(elOptNew, regionList.options[0]);
		} else {
			regionList.add(elOptNew, 0);
		}

		regionList.options[0].selected = true;
		regionList.disabled = true;			
	} else {
		if (lastRegionIndex != -1) {
			document.getElementById('regionList').disabled = false;
			regionList.remove(0);
			regionList.options[lastRegionIndex].selected = true;
		}
	}
}
window.onload = updateRegion;