seting the time zone in the server

hi, everybody

i've reading the pg users manual and in datatype-datetime.html it says
that the TZ environmet variable sets the time zone for the postmaster
backend at startup, and i'm trying to do this exactly to avoid some date
problems in my application.

i've set this variable in the .bash_profile of the postgres user and in
the /etc/rc.d/init.d/pstgresql script, but when inserting or querying
the data, i appears with a different timezone based on the date

so, can anyboby please give me some pointers about how to set this
variable in the ritght form, it would be greatly appreciated :)

i'm using pg 7.2.2-1PGDG on a redhat 7.1 system