var navDOM;
var announceDOM;
var aboutDOM;
var targetBlockHeight;

function findHeight (objectID) {
	var dom = findDOM(objectID, 0);
	if (dom.offsetHeight) {
		return dom.offsetHeight;
	}
	if (dom.clip.height) {
		return dom.clip.height;
	}
	return (null);
}

function setBlockHeight () {
	navDOM = findDOM('nav');
	targetBlockHeight = navDOM.style.height;
	announceDOM = findDOM('announce');
	aboutDOM = findDOM('about');
	announceDOM.style.height = targetBlockHeight + "px";
	aboutDOM.style.height = targetBlockHeight + "px";
	}