function changeObjectVisibility(objectId, newVisibility) {
	// get a reference to the cross-browser style object and make sure the object exists
  var styleObject = getStyleObject(objectId);
  if(styleObject) {
		styleObject.visibility = newVisibility;
		return true;
  } else {
		// we couldn't find the object, so we can't change its visibility
		return false;
  }
} // changeObjectVisibility

function getStyleObject(objectId) {
	// cross-browser function to get an object's style object given its id
  if(document.getElementById && document.getElementById(objectId)) {
		// W3C DOM
		return document.getElementById(objectId).style;
  } else if (document.all && document.all(objectId)) {
		// MSIE 4 DOM
		return document.all(objectId).style;
  } else if (document.layers && document.layers[objectId]) {
		// NN 4 DOM.. note: this won't find nested layers
		return document.layers[objectId];
  } else {
		return false;
  }
} // getStyleObject