svndump | svndumpfilter
Just a snippet for latter reference:
sudo -u apache -h nice svnadmin dump -r 18000:48135 //path/to//svnroot 2>fff.svnadmin.err | svndumpfilter—renumber-revs include sites/production/fff.org sites/devel/fff 1>fff.svndump 2>fff.dumpfilter.err &