timezone problem

I have just come across an weird datetime representation problem:

Under two BSD/OS machines, running 6.4.2. I get these two results:

customer=> select '28-03-1999'::datetime;
?column?
----------------------------
Sun 28 Mar 00:00:00 1999 EET
(1 row)

and

customer=> select '28-03-1999'::datetime;
?column?
-----------------------------
Sun 28 Mar 02:40:50 1999 EEST
(1 row)

The difference is... in the /etc/localtime file. The 'right' file is actually
quite older (the system has been upgraded from earlier versions several times
and the /etc/localtime is dated Oct 8 1996). The 'wrong' file is what recent
versions of BSD/OS install (at least after BSD/OS 3.0) for 'Europe/Sofia'.

Could some expect in datetime/timezone representation look at this - I am
attaching the two /etc/localtime files.

Regards,
Daniel