perl auth fails after upgrade to svn 1.7.5

Hey everyone,
We're currently running Apache 2.2.x on an OS X server with SVN 1.6.x
and have a mod_perl based authentication handler for SVN repo access.
It works fine and has for many months. When we upgrade to 1.7.x, our
commits fail with an Apache 500 error, and the logs show:
[Wed May 16 22:38:58 2012] [error] Subroutine fatal redefined at
/Library/Apache/HTTPD/2.2.11-flock/Perl/lib/perl5/site_perl/5.8.9/darwin-thread-multi-2level/APR/Error.pm
line 41.\nCompilation failed in require at (eval 22) line 1.\n

If we disable the new httpv2 that comes with 1.7.x all this goes away
and everything works exactly as it did under 1.6.x. We are not nesting
<Location> directives, and that's the only real issue I've found so
far that is similar to ours in the mailing list archive.

Where do I begin troubleshooting this?

-- 
Douglas J Hunley (doug.hunley_at_gmail.com)
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