Subversion code refresh failing to pick up new revisions

I've got an issue (previously mentioned in comments to BAM-871) where new revisions in a SVN repository cause the build to sit in a loop during code refresh with the following message:

30-Mar-2007 08:04:03 Failed to get the build source code:ActiveRecord-JDBC - Trunk
30-Mar-2007 08:04:04 Updating Subversion source code from version 408 to version 409
30-Mar-2007 08:04:04 Cleaning up subversion repository due to previous RepositoryException
30-Mar-2007 08:04:05 Cleanup of completed
30-Mar-2007 08:04:06 Failed to get the build source code:ActiveRecord-JDBC - Trunk
30-Mar-2007 08:04:07 Updating Subversion source code from version 408 to version 409
30-Mar-2007 08:04:07 Cleaning up subversion repository due to previous RepositoryException
30-Mar-2007 08:04:08 Cleanup of completed

The respository uses svn:// and svn+ssh:// URLs, which both exhibit this problem.

The build is located at: http://jruby.thresher.com/browse/ARJDBC-TRUNK

Server log attached. Let me know if you want a login to the server so you can examine or tweak the build configuration.