How do I get a fault-tolerant web service client?

Question

Is there any framework, which generates fault-tolerant web service clients? That means I don't have to regenerate the classes because of minor changes. Any programming language would be fine as a source of inspiration.

Following changes of the web service shouldn't need a regeneration of the client:

1. New optional method parameters.
2. Mandatory method parameters become optional.
3. Optional method parameters are omitted.
4. Mandatory method parameters are omitted.
5. New fields in responses.
6. Required response fields are omitted. (I want to handle that in code.)

Please add the case numbers, which could be handled by your solution, to your answer. And add a case if I missed one.