xntp mystery solved: POSIX timezone brain damage

[Randy Gobbel <gobbel-no.junk.mail@see.message.body>]

[For anti-spam purposes, my email address does not appear in canonical form
in this message, but if you're not trying to sell me anything, I welcome
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After digging around a bit more, I discovered that the 20-second offset is
due to overzealous compliance with a broken POSIX requirement in version
7.55 of the timezone package.  Apparently the POSIX committee, in a moment
of idiocy, decreed that POSIX time leave off the leap seconds that have
been added to UTC periodically since 1972.  There have been 20 of them,
leading to the 20-second discrepancy.  It appears that this breakage will
be remedied in the next release of timezone.  The interim cure is to revert
to version 7.48-3, in the stable distribution.

-Randy