Timezones on Tru64 (Digital Unix)

'set time zone 'GMT';', or any other 'set time zone' (even with numeric time
zones), is completely ignored on my Tru64 machine (I always get dates in local
time, UT+2). On Debian, everything is fine.

Did I forget something when compiling PostgreSQL? Is there something broken on
Tru64?

PostgreSQL 6.5. config.status follows:

./configure  --with-template=alpha_cc --with-CC=cc --without-CXX \
     --enable-locale --enable-cassert \
     --with-perl --with-tcl --with-jdbc \
     --with-x --with-pgport=5435