Form.Element.process = function(element) {
	element.observe('focus', function(event) {
		var element = event.element();
		if (element.value != element.defaultValue || element.cleared) return;
		element.clear();
		element.cleared = true;
	})
}

Event.observe(window, 'load', function() {
	$(document.body).select('.clearonfocus').each(function(item) {
		Form.Element.process(item);
	})
});