Create a Web Service from a view fails with error "Unexpected exception processing roots. "

Import a physical relational model, create a view model directly from the physical model, Right click on the view> Modeling > Create Web Service.
and you get:
Click "Details" button below or see the log for more information
Unexpected exception processing roots.
Invalid root object of type com.metamatrix.metamodels.relational.impl.ViewImpl in Xsd Generator.