read-only repository view

We would like to have a version of our SVN repository available
read-only over HTTP.

I currently have it setup using:
<Location /svn>
         DAV svn
         SVNPath /jasig/svn/jasig

<LimitExcept GET PROPFIND OPTIONS REPORT>
             Require valid-user
</LimitExcept>
</Location>

Which works but I get 500 errors instead of a 401 or 403 like I'd expect:

commit -m "NOJIRA test"
/home/edalquist/JavaClasses/workspace/PersonDirectory_trunk_RO/README.txt
     RA layer request failed
svn: Commit failed (details follow):
svn: Server sent unexpected return value (500 Internal Server Error) in
response to MKACTIVITY request for
'/svn/!svn/act/2348c9db-53b5-4d4b-852a-8cb5d0c4c071'

Is there a better way to have a read-only view of a repository?

-Eric