issue-21 / importing multiple versions of the same ontology

The last specific proposal from Peter:

http://lists.w3.org/Archives/Public/public-owl-wg/2008Apr/0212.html

Says:

> An ontology SHOULD NOT import multiple versions of the same  
> ontology, i.e., different ontology documents with the same ontology  
> URI but that
> do not share an owl:versionInfo annotation value.


However, the syntax document currently says:
> The OWL 2 specification provides no means for checking whether O is  
> compatible with the actually imported ontology versions.  
> Furthermore, if the ontologies imported into O additionally import  
> other ontologies, it is possible for O to import two different,  
> possibly incompatible, versions from the same ontology series. OWL  
> 2 provides no built-in means for detecting such situations.  
> Extensions providing such a mechanism, however, can be implemented  
> on top of OWL 2 import mechanism presented here.
>
>

-Alan