certification marking for email messages

I would like a plugin to outlook that put a certification marking for email messages' sending date, "a stamp" that warrants the sending and the integrity of electronic mail messages. The plugin/aplication must places an "electronic stamp" on an electronic document, such as an email message, and assures the veracity of the sending time and date of the document as well as the integrity of its content. This marking will contain several information regarding message transactions, allowing both the sender and the receiver to verify the sending date of electronic mail, its subject and attached documents to be delivered to receivers. This aplication/plugin must allow the users of my site to proof that they have sent their messages because as the message goes through the Internet it can get lost or be retained in a server for a certain period of time, making it impossible to assure that the deadline requirements are fulfilled. ## Deliverables 1) Complete and fully-functional working program(s) in executable form as well as complete source code of all work done. 2) Deliverables must be in ready-to-run condition, as follows (depending on the nature of the deliverables): a) For web sites or other server-side deliverables intended to only ever exist in one place in the Buyer's environment--Deliverables must be installed by the Seller in ready-to-run condition in the Buyer's environment. b) For all others including desktop software or software the buyer intends to distribute: A software installation package that will install the software in ready-to-run condition on the platform(s) specified in this bid request. 3) All deliverables will be considered "work made for hire" under U.S. Copyright law. Buyer will receive exclusive and complete copyrights to all work purchased. (No GPL, GNU, 3rd party components, etc. unless all copyright ramifications are explained AND AGREED TO by the buyer on the site per the coder's Seller Legal Agreement). ## Platform windows 98, xp & vista, outlook & outlook express