When I attempt to checkout:
svn checkout svn+ssh://serveradmin%foo@foo.com/home/87292/data/svn/repository/trunk .
I get this (unhelpful) er
I suspect Joel and Andy have it right.
You can use the ssh verbose flag to help figure out these kind of problems.
export SVN_SSH="ssh -v " svn checkout svn+ssh://serveradmin%foo/blah blah blah