code: private function _initProperties()
  	{
  		foreach ($this->_defaultValues as $k => &$v) {
  			/**
  			 * All properties, except resources, are now objects.
  			 * Clone the default/original value back to the original property.
  			 */
  			if (is_object($v)) {
  				$this->{$k} = clone $v;
  			}
  		}
  	}
docs: Should be called after _initMetaData().