pepsrv:~# tzselect 
Please identify a location so that time zone rules can be set correctly.
Please select a continent or ocean.
 1) Africa
 2) Americas
 3) Antarctica
 4) Arctic Ocean
 5) Asia
 6) Atlantic Ocean
 7) Australia
 8) Europe
 9) Indian Ocean
10) Pacific Ocean
11) none - I want to specify the time zone using the Posix TZ format.
#? 8
Please select a country.
 1) Aaland Islands        18) Greece                35) Norway
 2) Albania               19) Guernsey              36) Poland
 3) Andorra               20) Hungary               37) Portugal
 4) Austria               21) Ireland               38) Romania
 5) Belarus               22) Isle of Man           39) Russia
 6) Belgium               23) Italy                 40) San Marino
 7) Bosnia & Herzegovina  24) Jersey                41) Serbia
 8) Britain (UK)          25) Latvia                42) Slovakia
 9) Bulgaria              26) Liechtenstein         43) Slovenia
10) Croatia               27) Lithuania             44) Spain
11) Czech Republic        28) Luxembourg            45) Sweden
12) Denmark               29) Macedonia             46) Switzerland
13) Estonia               30) Malta                 47) Turkey
14) Finland               31) Moldova               48) Ukraine
15) France                32) Monaco                49) Vatican City
16) Germany               33) Montenegro
17) Gibraltar             34) Netherlands
#? 37
Please select one of the following time zone regions.
1) mainland
2) Madeira Islands
3) Azores
#? 1

The following information has been given:

        Portugal
        mainland

Therefore TZ='Europe/Lisbon' will be used.
Local time is now:      Sat Jun 30 12:33:11 WEST 2007.
Universal Time is now:  Sat Jun 30 11:33:11 UTC 2007.
Is the above information OK?
1) Yes
2) No
#? 1

You can make this change permanent for yourself by appending the line
        TZ='Europe/Lisbon'; export TZ
to the file '.profile' in your home directory; then log out and log in again.

Here is that TZ value again, this time on standard output so that you
can use the /usr/bin/tzselect command in shell scripts:
Europe/Lisbon
pepsrv:~# date
Sat Jun 30 07:33:25 EDT 2007
pepsrv:~#