function chose_prop(form) {
	if (form.development.selectedIndex == 0) {
		var td = document.getElementById('selector');
		var s = document.createElement('span');
		s.setAttribute('class', 'alert');
		var t = document.createTextNode('!!');
		s.appendChild(t);
		td.appendChild(s);
		return false;
	}
	return true;
}