DBI and Pg error

Some friends said this list is the best place to ask my questions regarding
BSDI/postgresql/DBI because some of you are BSDI expertises.

Basically, I installed postgresql, DBI and Pg and test it. My script works fine
locally and doesn't work as a CGI. I already asked several lists but so far I
can not fix it.

I run as root user in my BSDI 4.1/Apache 1.3.9 server. My perl is 5.005_03
My postgresql 6.5.3 was installed in the default location: /usr/local/pgsql
I run postmaster with -i option. Actually I use su - postgres in my rc.local file
to run postmaster automatically when the server startup. I also setup .bashrc
.bash_profile with the required env variables setup in both postgres and
root home.

For the database access, I include following several line in my pg_hba.conf
file to make it works with every one.

host all trust
host all 127.0.0.1 255.255.255.255 trust
host all 0.0.0.0 0.0.0.0 trust

I install DBI 1.13 and DBD:Pg 0.93 with no error message follow exactly the
README. All test was passed.

I created a testing database, a testing table and insert some records.
I use some perl scripts to test it. The script works locally and retrieve all the
records from the table. When I run it as a cgi, it doesn't work. When I didn't
set the required env variables, locally I get the same error message. That's
why I guess it could be an env variable problem. (If the DBI/DBD is not installed
correct, why it works locally??? !!!) I have tried to set the ENV with CGI, the
problem is still. The error message is always the same as below:

install_driver(Pg) failed" Can't load '/usr/libdata/perl5/site_perl/i386-bsdos/auto/DBD/Pg/Pg.so'
for module DBD::Pg: File not found at /usr/libdata/perl5/5.00503/i386-bsdos/DynaLoader.pm line 169.

I checked the two files, they all exist!

I got confused here. I can not figure out what's wrong. Some friend from the list said this
may be a installation problem and I need to reinstall perl. But why the DBI works fine locally
but not cgi.

Sorry for post so long here. But it's really important to me and I have to fix it ASAP!!!.

Any repsonse is very thankful.

Jim