public function renameProperty( $key, $new, $section = NULL )
	{
		if( $this->usesSections() )
		{
			if( !$this->hasProperty( $key, $section ) )
				throw new InvalidArgumentException( 'Key "'.$key.'" is not existing in section "'.$section.'"' );
			$this->properties[$section][$new]	= $this->properties[$section][$key];
			if( isset( $this->disabled[$section][$key] ) )
				$this->disabled [$section][$new]		= $this->disabled[$section][$key];
			if( isset( $this->comments[$section][$key] ) )
				$this->comments [$section][$new]	= $this->comments[$section][$key];
			$this->renamed[$section][$key] = $new;
			return is_int( $this->write() );
		}
		else
		{
			if( !$this->hasProperty( $key ) )
				throw new InvalidArgumentException( 'Key "'.$key.'" is not existing' );
			$this->properties[$new]	= $this->properties[$key];
			if( isset( $this->disabled[$key] ) )
				$this->disabled[$new]		= $this->disabled[$key];
			if( isset( $this->comments[$key] ) )
				$this->comments[$new]	= $this->comments[$key];
			$this->renamed[$key]	= $new;
			return is_int( $this->write() );
		}
	}