How do I get bzr diff to tell me the paths?

[Lennart Borgman]

I do something like this when building Emacs

    cd bld\emacs\emacsw32
    bzr diff --old ..\trunk --diff-options="-b -u" > %diff-file%

It gives me a diff, but the file names are hard to distinguish, they
look like this:

  === modified file 'lib-src/emacsclient.c'
  --- lib-src/emacsclient.c     2010-04-02 03:10:33 +0000
  +++ lib-src/emacsclient.c     2010-04-07 09:54:28 +0000

I would rather have a little bit more of the paths. Is that possible
in some way?