SVN and Postgres 8.3

We installed 8.3.7 on a new server. Some of the config changes such as
tracker_acvitity etc are nice.

But big problem. When I start SVN on this machine (which we need!) I
see this error:

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svn: error while loading shared libraries: libpq.so.4: cannot open
shared object file: No such file or directory
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I am unable to install the library "libpq.so.4" due to dependency errors.

Upon some digging, it seems this is because the PostgreSQL has
something to do with this, as the libraries "libpq.so.5" and
"libpq.so.5.1" are already present in the server. This is the reason
why we are unable to install the library "libpq.so.4".

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[snoff] ~ > rpm -ql postgresql-libs-8.3.7-1PGDG.rhel5 | grep libpq.so
/usr/lib64/libpq.so.5
/usr/lib64/libpq.so.5.1
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My question: how can I use PostgreSQL 8.3 and SVN on the same server?
Has someone figured out how to fix this situation? I'm on CentOS 5 x64
bit.

Thanks!