If I understand, you don't want to expose superMethod1() as a web method in your BeanImp, and you don't want to change the implementation in the BeanImp?!
As far as I know, you can do what Noni Singh said and call the super method from inherited one! I believe in that way the method in BeanImp will not be exposed as a web method,
and you will get the complete implementation of the superMethod1() from the Base class.
Sorry if I misinterpreted the question.