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

Hi,

with Silva 1.0 :

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. BUT when I try to access 
it in a pagetemplate with:
  tal:attributes="
  class python: here.get_metadata_element('zwec','css_class')"

I get an attribute error "zwec" if I replace 'zwec' with 'silva-extra'
no attribute error.

What I am missing here ?
-- 
Mit freundlichen Grüßen                                Joachim Schmitz
......................................................................
AixtraWare eK ..Joachim Schmitz ..www.aixtraware.de ..t: +49-2464-8851
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