[CentOS] RPM conflicts - help!

I'm building a database/application server with a Dual-Opteron 64 bit system.

I need to run PHP4, Apache, and Postgres 8.1, but I'm having conflicts with Postgres 8.1 and PHP 4 that comes with CentOS.

History: 1) I installed Apache and PHP with yum. 2) I then installed PostgreSQL 8.1 RPMs from the PG website. 3) Then, I tried to install php-pgsql with yum - and it didn't work, complaining about pgsql.so.3. So, I installed with --nodeps and symlinked the /usr/lib64/libpq.so.4 -> /usr/lib64/libpq.so.3.

Now, PHP and PGSQL work without any problems. But now, I can't do a yum update - it still complains about pgsql.so.3!

What can I do to resolve this?

Thanks, -Ben