I am not sure whether this is a bug or I am misunderstanding
something and trying to do something stupid.

A dataset has two primary keys (both Int64). Adding records to the
dataset via a grid works fine. A Delete button looks at the current
record in the grid and if the dataset is in insert mode it performs a
cancel and if not a delete. This all works fine.

If I enable DML caching and set the dataset to announce all inserts,
edits and deletes, then when I delete a record from the grid, after
it has been posted - so the dataset is not in dssInsert mode - and
the DML caching will have been invoked - performing the delete causes
an "Invalid reference for delete" error message. I can reproduce
this with other datasets at will so I don't think it is anything
specific to the dataset.

This is using Delphi 6 and IBO4.2Ea