Never record undo information for session or data import for session, it may causes unlimited database size expansion while it makes no sense to undo this kind of changes. For data import, they are created programatically hence we may not want to undo this either.

addressbook
basket
blog
book
calendar
comment
company
email
file
folder
i18ncontent
keyword
link
mailinglist
person
tag
timeseries
vcsfile