Clock : can't handle winter/summer time automatically ?

[Vincent Trouilliez]

Last week-end we switched to summer time here... on sunday at 2AM... it
was 3AM. 
But when I started the computer at 7AM, the clock didn't go forward one
hour as expected, so I had to do it manually.

I think Windows 95 when I had it, could do it, so I thought a 2006 Linux
(running Dapper), would be able to do it too ! Especially now that the
machine has broadband and is connected permanently, so no problem
gathering data about what country changes when, if at all etc.

there must be a reason why it didn't handle it... just wondering what
the hell it might be... ideas ???

Or is there something special I should do to enable automatic time
changes ? I didn't see any obvious setting in the clock preferences in
any case :-/

--
Vince