Private method in groovy is not private

Searching for [groovy] private reveals:

groovy call private method in Java super class

What does 'private' mean in Groovy?

How to define private getter method in Groovy Bean?

It's not clear if it is a bug or by design, but it is going to get looked at again in Groovy 2.0

There is defect on that in Groovy issue tracking system and that defect is still open.