11.2.1.8 sop:datatype uses non-xsd "integer" type.

Hello,

The example from section 11.2.1.8 uses a non-xsd datatype URI.
Is this intentional?

PREFIX foaf: <http://xmlns.com/foaf/0.1/>
SELECT ?name ?size
 WHERE ( ?x foaf:name  ?name )
       ( ?x foaf:shoeSize  ?size )
   AND datatype(?size) == <http://...integer>

Thanks,

-bryan