private function addConverter($word, $modifiers, $option) {
 		$formattingInfo = $this->parseModifiers($modifiers);
		$option = trim($option, "{} ");
		
		if (isset($this->converterMap[$word])) {
			$converter = $this->getConverter($word, $formattingInfo, $option);
			$this->addToChain($converter);	
		} else {
			throw new \n2n\log4php\LoggerException("log4php: Invalid keyword '%$word' in converison pattern. Ignoring keyword.", E_USER_WARNING);
		}
	}