function validatePersonalizationForm(f) {
	var checkedItems = 0;
	for (var i = 0; i < document.catForm.length; i++) {
		if (document.catForm[i].checked)
			checkedItems++;
	}
	if (checkedItems > 3) {
		alert('Du kannst maximal 3 Kategorien wählen.');
		return false;
	}
	else if (checkedItems < 1) {
		alert('Bitte wähle mind. 1 Kategorie');
		return false;
	}
	return true;
}

function submitPersonalizationForm() {
	if (validatePersonalizationForm(document.catForm)) { 
		document.catForm.submit(); 
	}
}