need help on my postgres on centos 4.3

I am totally new to postgres and need help to fix a problem comes from rake command. This morning I installed postgres 8.2 on my centos 4.3 box.

the steps I used to install postgres are as follows:

1) wget postgresql-8.2.2.tar.gz from postgres.org 2) tar -zxf postgresql-8.2.2.tar.gz 3) yum install flex 4) ./configure --prefix=/usr/local/pgsql --without-readline 5) gmake 6) gmake install 7) export POSTGRES_INCLUDE=/usr/local/pgsql/include/ 8) export POSTGRES_LIB=/usr/local/pgsql/lib/ 9) export LD_LIBRARY_PATH=/usr/local/pgsql/lib/ 10)gem install ruby-postgres

everything was fine. after that, I started postgresql and created a test db:

CREATE DATABASE "test_developent" WITH ENCODING='UNICODE' OWNER=postgres;

it was ok too.

then, rails test --database=postgresql

it was successfully as well.

when I test rake db:migrate, I got the following error message:

(in /usr/local/html/test) rake aborted! libpq.so.5: cannot open shared object file: No such file or directory - /usr/lib64/ruby/gems/1.8/gems/ruby-postgres-0.7.1.2006.04.06/./postgres.so

I found postgres.so is located at folder ruby-postgres-0.7.1.2006.04.06, no idea why there is a "./" before postgres.so. any one could help me out? thanks.