Schema reference in Webmethods generated SOAP documents

We are working on a SOAP-based B2B integration project, where we generate SOAP messages using createSOAPData and addBody
Webmethods Internal Server 6.0.1 generates SOAP messages which reference the following schema:
http://www.w3.org/1999/XMLSchema
What configuration should I do to change this reference to:
http://www.w3.org/2001/XMLSchema

Andi Giri
B2B Solutions Architect
BCE Emergis