howto access the metadata of an index doc

that was  "what to do, to use a new meta-data-set ?"

I created a new meta-data-set with Namespace URI: 
http://infrae.com/namespaces/metadata/zwec, and Namespace Prefix: 
"zwec", added two fields to it, and activated it. I edited the
Content Type Metadata Mapping for a Silva Document Version to 
"silva-content, silva-extra, zwec"

After that the new metadata-set shows in the properties for each silva 
document version. I can edit the new metadata.

I tried this in the index document of a publication. The snipplet in my 
content.html.pt looks like this:

<tr metal:fill-slot="main"
    tal:define="view_method options/view_method"
   border="0" cellpadding="0" cellspacing="0" style="width:768px">
<td colspan=1 class="ccc"
	  tal:attributes="colspan python: 
model.get_metadata_element('zwec','grid_width');
	  class python: model.get_metadata_element('zwec','css_class')"
tal:content="structure python:getattr(model, view_method)()">
</td>
</tr>

this fails cause the model is the publication not the index.pt, the 
publication has no metadata set "zwec". If I write:
tal:attributes="colspan python: 
model.index.get_metadata_element('zwec','grid_width')"

it works for index, but not for all other docs.

So the question is how do I get the actuall published document in this 
case ?

-- 
Mit freundlichen Grüßen                                Joachim Schmitz
......................................................................
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