CentOS / RHEL 4 ship with a rather dated version of Subversion - 1.1.4, and according to a result from google, upgrading it to the latest stable was not possible due to incompatibility with the shipped version of APR [0.9.4]. However, this might not be the case.
The above link from the centos mailing list pointed me to RPMForge, a third-party repository for CentOS which was said to have version 1.3.2. I set this up (and had to unprotect the base and update repos) and found that svn 1.4.3 was available without any modifications to APR. The only other update was to the apache svn module
mod_dav_svn which was also updated to the same version.
All appears to be going well - El perfecto!
Anyways, just wanted to put this out there in case others are in the same boat as I was. From what I understand, RHEL 5 / CentOS 5 will also ship only with svn 1.3.2 :P