Actually, there is an assert when the collection id are not the same you
are store in your cache. I work on Zanshin and I can move an Item from a
Collection to another and i can reproduce the same behaviour with akonadiconsole.

This path remove the assert on this case and avoid a crash when we move
the item to a different collection.

I add kdepim in groups because a part of the code comes from kdepim/akonadi/kcal