How can I customise the namespace prefixes in Metro/JavaEE auto-generated WSDL?

@XmlSchema (
  xmlns = {
    @XmlNs(prefix = "so",
               namespaceURI="http://stackoverflow.com/questions/358991")
  )
)

<schema
    xmlns:so="http://stackoverflow.com/questions/358991"
    targetNamespace="http://stackoverflow.com/questions/358991">