WSDL versioning

A few weeks ago I was asked how to version WSDLs. Well I had no idea, as I have never needed to do that. I worked in tightly environment where new versions of consumers and publishers were deployed at the same time. Sometimes not very successfully, but we didn't need to support multiple versions.
  I found the problem of WSDL interesting so I start googling and here are some information I found. The WSDL doesn't support versioning, so there are couple of ways how to do it.

• Including service version in URI
• Versioning using namespace (more information can be found here)
• Using UDDI (more can be found here)

 I personally prefer versioning using namespace.