Today I patched, and it broke email once again. As on several previous occasions, perl modules were broken, amavisd-new was throwing misleading errors on startup, and I had to reinstall Scalar-List-Utils to get rid of complaints about Compress::Zlib.

This time, however, I decided to upgrade amavisd-new in hopes the new version would be smarter about the (bogus) perl module complaints at startup. I also tried using yum to install some of the perl module dependencies, which entailed reinstalling spamassassin. Alas, amavisd-new-2.6.4 is no smarter, but either amavisd-new or spamassassin introduced a new dependency on Mail::DKIM, which requires the Crypt-OpenSSL-Random perl module. I tried getting them through cpan, but it kept choking -- apparently Crypt-OpenSSL-Random requires the openssl-devel RPM on CentOS, but isn't smart enough to throw a clear error demanding it.

I never did figure out where Mail::DKIM was enabled, or how to disable it, but I seem to have found a much better solution.

amavisd-new is not in the base RHEL (or CentOS) repositories, so the CentOS wiki recommends getting it from RPMForge. This turned out to be pleasantly simple, and should prevent yum from breaking it in the future. Here's hoping, anyway!