RE: Users can't login to properties (meta-data) tab

Thanks to Clemens' hint I'm able now to provide the traceback:

Traceback (innermost last):
  Module ZPublisher.Publish, line 101, in publish
  Module ZPublisher.mapply, line 88, in mapply
  Module ZPublisher.Publish, line 39, in call_object
  Module Shared.DC.Scripts.Bindings, line 306, in __call__
  Module Shared.DC.Scripts.Bindings, line 343, in _bindAndExec
  Module Products.FileSystemSite.FSPageTemplate, line 191, in _exec
  Module Products.FileSystemSite.FSPageTemplate, line 124, in pt_render
  Module Products.PageTemplates.PageTemplate, line 96, in pt_render
   - <FSPageTemplate at
/silva_ethz/service_views/Silva/edit/Container/Publication/tab_metadata>
  Module TAL.TALInterpreter, line 189, in __call__
  Module TAL.TALInterpreter, line 233, in interpret
  Module TAL.TALInterpreter, line 406, in do_optTag_tal
  Module TAL.TALInterpreter, line 388, in no_tag
  Module TAL.TALInterpreter, line 233, in interpret
  Module TAL.TALInterpreter, line 670, in do_useMacro
  Module TAL.TALInterpreter, line 233, in interpret
  Module TAL.TALInterpreter, line 693, in do_defineSlot
  Module TAL.TALInterpreter, line 233, in interpret
  Module TAL.TALInterpreter, line 408, in do_optTag_tal
  Module TAL.TALInterpreter, line 393, in do_optTag
  Module TAL.TALInterpreter, line 388, in no_tag
  Module TAL.TALInterpreter, line 233, in interpret
  Module TAL.TALInterpreter, line 670, in do_useMacro
  Module TAL.TALInterpreter, line 233, in interpret
  Module TAL.TALInterpreter, line 408, in do_optTag_tal
  Module TAL.TALInterpreter, line 393, in do_optTag
  Module TAL.TALInterpreter, line 388, in no_tag
  Module TAL.TALInterpreter, line 233, in interpret
  Module TAL.TALInterpreter, line 701, in do_defineSlot
  Module TAL.TALInterpreter, line 233, in interpret
  Module TAL.TALInterpreter, line 408, in do_optTag_tal
  Module TAL.TALInterpreter, line 393, in do_optTag
  Module TAL.TALInterpreter, line 388, in no_tag
  Module TAL.TALInterpreter, line 233, in interpret
  Module TAL.TALInterpreter, line 408, in do_optTag_tal
  Module TAL.TALInterpreter, line 393, in do_optTag
  Module TAL.TALInterpreter, line 388, in no_tag
  Module TAL.TALInterpreter, line 233, in interpret
  Module TAL.TALInterpreter, line 670, in do_useMacro
  Module TAL.TALInterpreter, line 233, in interpret
  Module TAL.TALInterpreter, line 408, in do_optTag_tal
  Module TAL.TALInterpreter, line 393, in do_optTag
  Module TAL.TALInterpreter, line 388, in no_tag
  Module TAL.TALInterpreter, line 233, in interpret
  Module TAL.TALInterpreter, line 408, in do_optTag_tal
  Module TAL.TALInterpreter, line 393, in do_optTag
  Module TAL.TALInterpreter, line 388, in no_tag
  Module TAL.TALInterpreter, line 233, in interpret
  Module TAL.TALInterpreter, line 636, in do_condition
  Module TAL.TALInterpreter, line 233, in interpret
  Module TAL.TALInterpreter, line 636, in do_condition
  Module TAL.TALInterpreter, line 233, in interpret
  Module TAL.TALInterpreter, line 459, in do_setLocal_tal
  Module Products.PageTemplates.TALES, line 221, in evaluate
   - Line 179, Column 10
   - Expression: <PythonExpr
request.model.service_renderer_registry.getFormRenderersList(request.model.m
eta_type)>
   - Names:
      {'container': <DirectoryViewSurrogate instance at 43f72c50>,
       'context': <DirectoryViewSurrogate instance at 43f72c50>,
       'default': <Products.PageTemplates.TALES.Default instance at
0x40b7ff0c>,
       'here': <DirectoryViewSurrogate instance at 43f72c50>,
       'loop': <SafeMapping instance at 43e0c880>,
       'modules': <Products.PageTemplates.ZRPythonExpr._SecureModuleImporter
instance at 0x40b8632c>,
       'nothing': None,
       'options': {'args': ()},
       'repeat': <SafeMapping instance at 43e0c880>,
       'request': <HTTPRequest,
URL=http://cms02.ethz.ch:8083/silva_ethz/ETH/id_sites/edit/tab_metadata>,
       'root': <Application instance at 41551350>,
       'template': <FSPageTemplate at
/silva_ethz/service_views/Silva/edit/Container/Publication/tab_metadata>,
       'traverse_subpath': [],
       'user': lbenno}
  Module Products.PageTemplates.ZRPythonExpr, line 47, in __call__
   - __traceback_info__:
request.model.service_renderer_registry.getFormRenderersList(request.model.m
eta_type)
  Module Python expression
"request.model.service_renderer_registry.getFormRenderersList(request.model.
meta_type)", line 1, in <expression>
Unauthorized: You are not allowed to access 'getFormRenderersList' in this
context

Regards,
Benno