[tz] Non-valid timezones, is there a rule to remove them?

[Paul Eggert]

Fabiano Fidêncio wrote:
> Looking at the zone.tab file I can see a few timezones that, although valid
> in the past, they are not valid anymore. I can pick as example, reported on
> the GNOME Bugzilla[0], Asia/Novosibirsk, that used to be UTC+7, but
> nowadays is considered the same one than Asia/Almaty, which one is UTC+6.

This appears to be a problem with some mapping between MSDN and the tz 
database. If so, I suggest writing to whoever's maintaining that 
mapping. (The tz database itself does not contain the mapping.)