I recently set up browsing of a subversion repository in redmine but kept getting this annoying error:
The entry or revision was not found in the repository.
After a bit of googling and trying various things without success the thing that finally solved it was changing
SVN_BIN = "svn"
SVN_BIN = "/usr/local/bin/svn"
This is in FreeBSD, the location of the svn binary you want might of course differ.