onload = function() {
	if (document.getElementsByClassName == undefined) {
		document.getElementsByClassName = function(className) {
			var hasClassName = new RegExp("(?:^|\\s)" + className + "(?:$|\\s)");
			var allElements = document.getElementsByTagName("*");
			var results = [];

			var element;
			for ( var i = 0; (element = allElements[i]) != null; i++) {
				var elementClass = element.className;
				if (elementClass && elementClass.indexOf(className) != -1
						&& hasClassName.test(elementClass))
					results.push(element);
			}

			return results;
		}
	}
}

function activateTab(tabid) {

	var tabs = document.getElementsByClassName('tab');
	var texts = document.getElementsByClassName('tab_text');

	for ( var i = 0; i < tabs.length; i++) {

		if (tabs[i].id == tabid) {
			tabs[i].style.backgroundImage = 'none';
		} else {
			tabs[i].style.backgroundImage = 'url(/skins/images/verlag/default/tab.png)';
		}
	}

	for ( var k = 0; k < texts.length; k++) {
		if (texts[k].id == 'text_' + tabid) {
			texts[k].style.visibility = 'visible';
			texts[k].style.display = 'block';
		} else {
			texts[k].style.visibility = 'hidden';
			texts[k].style.display = 'none';
		}
	}
}