Greetings monks;

I'm trying to get a very simple timezone display going without having to install the rather heavy DateManip or DateTime groups of modules (Which seemingly require copious amounts of modules).
I live in CST, and the following works:

$ENV{TZ} = "America/New_York";
my $now_string = strftime "%a %b %e %H:%M:%S %Y %c", localtime;
print "$now_string\n";
[download]

Which prints:

Tue Nov  1 17:40:54 2005 Tue 01 Nov 2005 05:40:54 PM EST

However, if I try the following:

$ENV{TZ} = "America/Chicago";
my $now_string = strftime "%a %b %e %H:%M:%S %Y %c", localtime;
print "$now_string\n";

$ENV{TZ} = "America/New_York";
$now_string = strftime "%a %b %e %H:%M:%S %Y %c", localtime;
print "$now_string\n";
[download]

I get:

Tue Nov  1 16:41:08 2005 Tue 01 Nov 2005 04:41:08 PM CST
Tue Nov  1 16:41:08 2005 Tue 01 Nov 2005 04:41:08 PM EST

Which is clearly more than a little odd.
I'm not seeing an obvious difference here in methodology - which means that there's either a bug in localtime(), or I'm missing something - and I'm putting money on it being my problem.

I can, of course, move to using one of the larger modules - that is a valid option, but I'd prefer to not have to resort to doing so when it appears localtime() should be able to handle this properly.
(I'm on a Linux machine running Debian, if it helps)

My thanks;