Schema file names for wsdl-extensions seem inconsistent

In the namespace document at http://www.w3.org/2006/01/wsdl-extensions the
URL for the Dated Version of the XML schema file is:
http://www.w3.org/2006/03/wsdl-extensions.xsd

In the new namespace document at http://www.w3.org/ns/wsdl-extensions the
URL for the Dated Version is:
http://www.w3.org/2007/03/wsdl/wsdl20-extensions.xsd

Is this correct...with the "20" in the file name?

Note, in both documents the file name used for the Latest Version of the
schema is just 'wsdl-extensions.xsd' (without the "20").

John Kaputin.