function checkOptikerSearchForm(caller) {
	var parent = caller.parentNode;
	var children = parent.childNodes;
	//alert(children[2].name);
	var input = children[2];
	if (navigator.userAgent.indexOf('IE') != -1) {
		input = children[1];
	}
	if (input.name == 'tx_fesearchintable_pi1[zip]') {
		var re = /\D/
		if (re.exec(input.value)) {
			alert('PLZ field must contain only numbers, please fill this field correctly');
			return false;
		} else {
			return true;
		}
	} else if (input.name == 'tx_fesearchintable_pi1[location]') {
		var re = /\d/
		if (re.exec(input.value)) {
			alert('Ort field must contain only chars not numbers, please fill this field correctly');
			return false;
		} else {
			return true;
		}
	}
}