After upgrading svnadmin gives "Expected repository format '3' or '5'; found format '4'". My SVN repository is broken

Binary package hint: subversion

Before upgrading to maverick my SVN repository worked fine. It was served to users over the apache2 dav-svn module.

Since I have upgraded the repository does not work. My Apache2 error log contains:

[Mon Oct 11 16:52:14 2010] [error] [client 87.194.166.225] (20014)Internal error: Berkeley DB error for filesystem '/var/lib/svn/repository/db' while opening environment:\n
[Mon Oct 11 16:52:14 2010] [error] [client 87.194.166.225] Could not fetch resource information. [500, #0]
[Mon Oct 11 16:52:14 2010] [error] [client 87.194.166.225] Could not open the requested SVN filesystem [500, #160029]
[Mon Oct 11 16:52:14 2010] [error] [client 87.194.166.225] Could not open the requested SVN filesystem [500, #160029]

I tried running svnadmin recover:

# svnadmin verify /var/lib/svn/repository/db
svnadmin: Expected repository format '3' or '5'; found format '4'

It looks like the berkley DB version has been upgraded, without a way to upgrade existing databases.

Mine is a small repository, and I have a set of checkin dumps for everything in the repository, so I could just create a new repository, and load the checkin dumps to recreate my SVN database, but that is hardly a nice solution.

ProblemType: Bug
DistroRelease: Ubuntu 10.10
Package: subversion 1.6.12dfsg-1ubuntu1
ProcVersionSignature: Ubuntu 2.6.35-22.33-generic 2.6.35.4
Uname: Linux 2.6.35-22-generic x86_64
Architecture: amd64
Date: Mon Oct 11 17:13:56 2010
ProcEnviron:
 SHELL=/bin/bash
 PATH=(custom, user)
 LANG=en_GB.UTF-8
SourcePackage: subversion