XML-Schema for WSDD?

[W.Beck]

Hi folks,

I want to validate my deployment/undeployment descriptor files but so
far now I was not able to locate a schema for WSDD on the net. Where do
I find it? What'S the URL that goes into the
xsi:noNamespaceSchemaLocation attribute of the deployment/undeployment
root element?

thx
cu*
Willy