I like software that does stuff, but that extra stuff often comes with the added baggage of dependencies; especially in the RPM world. So I'm trying to install the newer Postgres libraries on my RHEL 5 box and postgres-libs is having a fit because APR-utils relies on libpq which is in that RPM. Of course, apr is a dependency for Apache so by removing postgres, I'd subsequently be axing most of the other software that I need on the system.
My best guess is that apr is included some bundled functionality that I'll never use but is none-the-less compiled against the libpq shared libraries. I'm glad I'm not the first person who has encountered this though. I found a tutorial that walks you through how to resolve this issue.