public function setChannel( $channel = NULL )
	{
		if( !is_string( $channel ) )
			$channel	= 'auto';
		$channel	= strtolower( $channel );
		if( !in_array( $channel, array( 'auto', 'console', 'html' ) ) )
			throw new OutOfRangeException( 'Channel type "'.$channel.'" is not supported' );
		if( $channel === "auto" ){
			$channel	= 'html';
			if( getEnv( 'PROMPT' ) || getEnv( 'SHELL' ) || $channel == "console" )
				$channel	= 'console';
		}
		$this->channel	= $channel;
	}