Can't browse instances of classes that use zope.interface.implementsOnly()

Apparently when you have

   class IFoo(Interface):
        pass

   class Foo(object):
        implements(IFoo)

   class IBar(Interface):
        pass

    class Bar(Foo):
        implementsOnly(IBar)

and when you register an adapter

     class FooAdapter(object):
        adapts(Foo)
        implements(ISomething)

then you can't use ISomething(Bar()) -- implementsOnly makes it forget not just the inherited interfaces, but also all the base classes! Is that intentional?

Partial fix for this committed in 8ed0dfb.

Correction: partial fix is in 729ef6d (I had to git commit --amend to fix a broken unrelated test).

This should be fixed in 0.16.3.

0.16.3 became 0.17.