function switchTeaser(nr, max) {

	for (var i=1; i<=max; i++) {
		var e = document.getElementById('startteaser_' + i);
		if (e != null) {
			e.style.display = 'none';
		}
	}
	var e = document.getElementById('startteaser_' + nr);
	if (e != null) {
		e.style.display = 'block';
	}
	else {
		return true;
	}
	return false;
}

function slideshow() {
	actPosition++;
	if (actPosition == 4) {
		actPosition = 1;
	}
	switchTeaser(actPosition, maxTeasers, 0);
}