In article <49CF36A1.8000500 / it.aoyama.ac.jp>,
  "Martin J. Dst" <duerst / it.aoyama.ac.jp> writes:

> I agree with Pavel. Japan also may be adapting daylight savings
> time sooner or later, so it might be a good idea to work on
> timezone-related problems in core Ruby soon.
>
> Updates of timezone information doesn't have to be frequent,
> for most purposes (work in a locality that doesn't change
> timezone rules), even no update is okay. To keep current
> for timezones world-wide, an update about once a month
> should be more than enough; governments change timezone rules
> at their will, but do it well in advance.

If you consider only a local timezone, current Ruby works
well if you update the timezone database in your OS.
-- 
Tanaka Akira