function css_change(obj,ext) {
	var cur_css	=	obj.className;
	if (cur_css.indexOf(ext)==-1) {
		obj.className	=	cur_css + ext;
	}
	else {
		obj.className	=	cur_css.replace(ext,'');	
	}
}

function checkall(obj , frm , name) {
	
	for (var i=0 ; i<frm.elements.length ; i++) {
		var e = frm.elements[i];
		if ((e.name != obj.name) && (e.type == 'checkbox') && (e.name == name)) {
			if (e.disabled == false) {
				e.checked = obj.checked;
			}			
		}		
	}
	
}

function check_form(frm) {
	for (var i=0 ; i<frm.elements.length ; i++) {
		var e = frm.elements[i];
		if (e.value=='') {
			alert('U heeft niet alle benodigde velden ingevuld! Probeer het nog enns...');
			e.focus();
			return false;
		}		
	}	
}