/a/b/c@myhost.test.ex -> /a/b/c
  transport = tf1
/x/y/z@myhost.test.ex -> /x/y/z
  transport = tf2
/a/b/c/@myhost.test.ex -> /a/b/c/
  transport = td1
/a/a/b//@myhost.test.ex -> /a/a/b//
  transport = td2