function toggleLayer(whichLayer)
{
	if (document.getElementById)
	{
		// this is the way the standards work
		var eleme = document.getElementById(whichLayer);
		if ( eleme != null && eleme.value != "" ) {
    		var style2 = document.getElementById(whichLayer).style;
    		style2.display = (style2.display == "block" ) ? "none":"block";
        }
	}
//	else if (document.all)
//	{
		// this is the way old msie versions work
//		var style2 = document.all[whichLayer].style;
//		style2.display = (style2.display == "block" ) ? "none":"block";
//	}
	else if (document.layers)
	{
		// this is the way nn4 works
		var style2 = document.layers[whichLayer].style;
		style2.display = (style2.display == "block" ) ? "none":"block";
	}
}