I've got a dump from svn < 1.6 and there are revision with path names, which are not encoded in UTF-8. svn fails with: svnadmin: Path '...' is not in UTF-8. It seems to be a rare problem, but some svn clients did not correctly encode path names in UTF-8 and svn < 1.6 did accept those revisions. The only known workaround yet is to take a (hex)editor and find and replace those failing revisions. This is hard to do on "big" dumps and i don't know how many failing path names my dump got ... may be a neverending story perhaps if there are many "incorrect" revisions. It would be good if svnadmin or some other tool can provide some options to do the recoding automatically by replacing those chars with a "best" guess or some default value (may have to be provided by the user), to be able to load such dumps without having to edit it via editor.
Original issue reported by tkrah