[Zope] Force ZCatalog to UTF-8

Hi all! How can I force ZCatalog to use only unicode strings (UTF-8)? I'm trying to change all zope to use these charset. For that I install Zope 2.9.1 and I change on zope.conf: rest-input-encoding utf-8 rest-output-encoding utf-8 default-zpublisher-encoding utf-8 but ZCatalog don't catalog unicode if the string is not an unicode string (at least I think so) Any idea? Thanks a lot! -- Mis Cosas http://blogs.sistes.net/Garito/