I see. There is code to decide the values for time.timezone, time.altzone and time.daylight that compares tm_gmtoff for Jan 1st of the current year to tm_gmtoff for July 1st; it uses this to decide whether DST is in effect and on which hemisphere you're on. I don't know why I didn't think of checking the tm_isdst flag instead, but either way the code would have failed for you prior to Jan 1st 07, because it could not have seen a difference if your timezone database was correct.  You're just lucky you weren't running CYGWIN; the code inside #ifdef __CYGWIN__ doesn't even entertain the possibility that there's life possible on the Southern hemisphere. ;-)

I think we should do two things; (a) export tm_zone and tm_gmtoff if they exist; (b) change the code that probes Jan 1st and Jul 1st of the current year to instead probe  4-6 spots starting today and covering the year forward.

Unfortunately tm_zone and tm_gmtoff appear glibc inventions, so for supporting Solaris, Windows etc. I think we still need these.  We really could use a module that accesses the entire timezone database but that's even more platform specific.

If you want this to happen, please lobby for someone to help out on python-dev or c.l.py; I'm kind of overcommitted. :-)