Unable to install DBD module

Hello,

I am trying to install the DBD module and having some problems...

-When trying to install 'DBD-Pg-0.95.tar.gz' I receive the following error
after running 'perl Makefile.PL':
"... Please set environment variables POSTGRES_INCLUDE and POSTGRES_LIB !"

-When trying to install 'DBD-Pg-0.73-1.i386.rpm' I receive the following
error:
"DBI is needed by DBD-Pg-0.73-1" [which is installed...] and "libpq.so.1 is
needed by DBD-Pg-0.73-1"

-When trying to install 'perl-DBD-Pg-0.91-2.i386.rpm' I receive the
following error:
"libpq.so.2.0 is needed by perl-DBD-Pg-0.91-2"

My setup is Redhat 6.2, Postgres 7.0.2-2,
also installed is DBI-1.14.
libpq.so.2.0 is located in '/usr/lib/',
libpq.so.1 is not installed on my system,
my ld.so.conf file has the following lines:
/usr/lib
/usr/include/pgsql/lib
/usr/include/pgsql/libpq
[+ others]

If anyone can help me with this I would be very grateful!

Thanks in advance,
Jim