reverse mapping for xsd:integer vs xsd:nonNegativeInteger

In http://www.w3.org/TR/owl-semantics/mapping.html, it says:

For the purposes of determining whether an RDF graph is an OWL DL  
ontology in RDF graph form, cardinality restrictions are explicitly  
allowed to use constructions like "1"^^xsd:integer so long as the  
data value so encoded is a non-negative integer.

Therefore, for backwards compatibility, should the reverse mapping  
explicitly have a mapping for the (non qualified) cardinality cases  
where it currently only says xsd:nonNegativeInteger?

-Alan