XForms and Undo

Hello;

Wondering if anyone has given thought on how XForms addresses the common
user need to "undo" a series of edits in historical sequence.

For example, through an XForm, a user is editing some important information,
realizes a mistake has been made, and needs to "undo" several of these
edits. The result of each undo is the changes made for that edit to the
XForms models are reversed. Perhaps some actions denote a commit point that
cannot be undone and clears all prior edits - for example a submit.

I can imagine this would be a very powerful feature for an XForms
implementation to provide to its users. This would be especially nice if the
Undo capability was done in such a way as to be zero effort for the XForm
author.

I believe end-users have come to expect undo from their commercial
applications (e.g. office productivity apps, etc.), so why not address this
requirment as part of the XForms spec? That way the behavior associated with
an Undo is consistent from an end-user perspective as well as an XForms
author perspective. Or if this does not need to be part of the spec perhaps
the spec can at least explicitly say its up to implementations to provide
this feature or not.

Has this been addressed or discussed explicitly by the XForms spec groups?

How about the XForms implementation community? Anyone stepping up to the
plate to provide this feature?

Thanks in advance,

Brian.