public function addField($label, $value, $checked = false, $meta = array())
    {
        $name = $this->getName();

        $objField = new GroupField($this->getRandomId($name), $name, $this->__type, $label, $value, $checked, $meta);
        $objField->setMeta("parent", $this, true);

        $this->__fields->addObject($objField);

        // *** Set the default value if "checked" is set.
		if ($checked) {
		    switch ($this->__type) {
		        case ValidForm::VFORM_CHECK_LIST:
		            $arrDefault = (is_array($this->__default)) ? $this->__default : array($this->__default);
		            $arrDefault[] = $value;

		            $this->__default = $arrDefault;

		            break;
		        default:
		            $this->__default = $value;
		    }
		}

        return $objField;
    }