php 4.2 postgresql 7.3 help

I'm using the redhat 8 php 4.2.2 installation and postgresql 7.3.1 rpm
from here:
ftp://ftp10.us.postgresql.org/pub/postgresql/binary/v7.3.1/RPMS/redhat-8.0

After upgrading to postgresql 7.3, my php-postgresql (pgsql.so)
extension will not load. This is the error in my apache error log:

PHP Warning: Unable to load dynamic library '/usr/lib/php4/pgsql.so' -
libpq.so.2: cannot open shared object file: No such file or directory in
Unknown on line 0

I looked for libpq.so.2 and could not find it, but I did find libpq.so.3
and libpq.so.3.0 in /usr/lib. I guess libpq.so.3 is from the postgresql
upgrade.

I know that I could probably downgrade to postgresql 7.2, but I would
like to keep 7.3 if possible. (I like the new drop column feature).

Any help would be much appreciated.

Randall