if (document.getElementById){
	layerRef="document.getElementById('";
	styleSwitch="').style";
}
else if (document.all){
	layerRef="document.all['";
	styleSwitch="'].style";
}
else if (document.layers){
	layerRef="document.layers['";
	styleSwitch="']";
}


function showLayer(layerName) {
 	eval(layerRef+layerName+styleSwitch+'.visibility="visible"');
}

function hideLayer(layerName) {
	eval(layerRef+layerName+styleSwitch+'.visibility="hidden"');
}