Problems with date and time

I have this problem that I can't understand. I have osx 10.5.4. The time in the computer is 06 october 2012 at 23:59 hs. When the time runs to 00:00 hs on 07 oct 2012, then the hour change to 1:00. I tried to put the hour in 12.00, but the day change to 6 oct, then I tried to change the day to 07 oct, but the our change to 23.00 (11.00 pm). I have the zone at Buenos Aires, and I don't understand why I can't set the time at 07 oct 2012 at 12.00 hour. I see that the same situation is on 06 oct 2013, or 02 oct 2012.

Can anybody helpme?

Thanks. Eduardo

Solution 1:

Sounds like Argentina does not follow DST, or does so on a very ad-hoc basis. This is possibly a bug in OS X (try updating your system) or perhaps an inevitable side-effect of not having a predictable schedule to code against.

Solution 2:

First thing I'd do is update your software. There's a reason the last release for Leopard is 10.5.8.