$ bzr push                                        
Using saved location: https://gkloss@gutefee.massey.ac.nz/svn/publications/trunk
HTTPS gkloss@gutefee.massey.ac.nz, Realm: 'GuteFee Subversion Repository' password:                                                                             
HTTPS gkloss@gutefee.massey.ac.nz, Realm: 'GuteFee Subversion Repository' password:                                                                             
bzr: ERROR: exceptions.AssertionError:                                          

Traceback (most recent call last):
  File "/usr/lib/python2.5/site-packages/bzrlib/commands.py", line 857, in run_bzr_catch_errors                                                                 
    return run_bzr(argv)                                                        
  File "/usr/lib/python2.5/site-packages/bzrlib/commands.py", line 797, in run_bzr                                                                              
    ret = run(*run_argv)                                                        
  File "/usr/lib/python2.5/site-packages/bzrlib/commands.py", line 499, in run_argv_aliases                                                                     
    return self.run(**all_cmd_args)                                             
  File "/usr/lib/python2.5/site-packages/bzrlib/builtins.py", line 802, in run  
    use_existing_dir=use_existing_dir)                                          
  File "/usr/lib/python2.5/site-packages/bzrlib/push.py", line 172, in _show_push_branch                                                                        
    stop_revision=revision_id)                                                  
  File "/usr/lib/python2.5/site-packages/bzrlib/decorators.py", line 138, in read_locked                                                                        
    result = unbound(self, *args, **kwargs)                                     
  File "/usr/lib/python2.5/site-packages/bzrlib/branch.py", line 1779, in push  
    _override_hook_source_branch=_override_hook_source_branch)                  
  File "/usr/lib/python2.5/site-packages/bzrlib/branch.py", line 1821, in _push_with_bound_branches                                                             
    result = self._basic_push(target, overwrite, stop_revision)                 
  File "/usr/lib/python2.5/site-packages/bzrlib/branch.py", line 1845, in _basic_push                                                                           
    result.tag_conflicts = self.tags.merge_to(target.tags, overwrite)           
  File "/usr/lib/python2.5/site-packages/bzrlib/tag.py", line 218, in merge_to  
    to_tags._set_tag_dict(result)                                               
  File "/usr/lib/python2.5/site-packages/bzrlib/plugins/svn/tags.py", line 140, in _set_tag_dict                                                                
    self.set_tag(k, v)                                                          
  File "/usr/lib/python2.5/site-packages/bzrlib/plugins/svn/tags.py", line 69, in set_tag                                                                       
    (from_bp, from_revnum, mapping) = self.repository.lookup_revision_id(tag_target)                                                                            
  File "/usr/lib/python2.5/site-packages/bzrlib/plugins/svn/repository.py", line 647, in lookup_revision_id                                                     
    return self.get_revmap().get_branch_revnum(revid, layout, project)          
  File "/usr/lib/python2.5/site-packages/bzrlib/plugins/svn/revids.py", line 154, in get_branch_revnum                                                          
    assert isinstance(mapping, BzrSvnMapping)                                   
AssertionError                                                                  

bzr 1.6.1 on python 2.5.2 (linux2)
arguments: ['/usr/bin/bzr', 'push']
encoding: 'UTF-8', fsenc: 'UTF-8', lang: 'en_NZ.UTF-8'
plugins:
  avahi                /usr/lib/python2.5/site-packages/bzrlib/plugins/avahi [0.3.0dev0]
  bzrtools             /usr/lib/python2.5/site-packages/bzrlib/plugins/bzrtools[1.6.0]
  dbus                 /usr/lib/python2.5/site-packages/bzrlib/plugins/dbus [unknown]
  gtk                  /usr/lib/python2.5/site-packages/bzrlib/plugins/gtk [0.95.0]
  launchpad            /usr/lib/python2.5/site-packages/bzrlib/plugins/launchpad [unknown]
  qbzr                 /usr/lib/python2.5/site-packages/bzrlib/plugins/qbzr [0.9.2]
  rebase               /usr/lib/python2.5/site-packages/bzrlib/plugins/rebase [0.3.0]
  svn                  /usr/lib/python2.5/site-packages/bzrlib/plugins/svn [0.4.13]
  xmloutput            /home/gkloss/.bazaar/plugins/xmloutput [0.8.2]
*** Bazaar has encountered an internal error.
    Please report a bug at https://bugs.launchpad.net/bzr/+filebug
    including this traceback, and a description of what you
    were doing when the error occurred.