Actually this was the wrong approach, too complicated.

Solved it by changing the email templates: - enable technical features for the users - goto Settings/Technical/Email/Templates) - Added CC ${user.email or ''}

So a copy of the email is being sent to the current logged in user. In Outlook you than can add a rule to automatically move the emails to the sent folder ... or a specific openerp folder ...

(this is just for testing - bare in mind when you update your openerp installation you will loose these changes - always put your changes in your own module!!!)