Can I display XML entities in an RDF tree?

I have a multi-language application in which I want to feed an RDF
tree with language-agnostic data from a server. The data in question
here is the status of a resource, which can only have a limited number
of values, i.e. "new" or "canceled".
What I've tried so far unsuccessfully was to try to get the entity
identifiers into the tree or by placing them directly into the RDF-XML
(which invalidated the XML as the entities are defined in a DTD file
in the XUL application) or by constructing them through variable
substitution in tree's template like <treecell value="&?variable^;"/>
(which invalidated the XUL).

Is there any way I can make use of the localized entities I've defined
in the client application?
The last resort would be to use images.

Thanks,
-Sebastian