11. The non-transitory computable readable medium of claim 10 wherein the header properties are simple mail transfer protocol (SMTP) x-header properties.
11. The non-transitory computable readable medium of claim 10 wherein the header properties are simple mail transfer protocol (SMTP) x-header properties. 13. The non-transitory computable readable medium of claim 11 further comprising adding visual markings to the message form selected from one or more security classification characteristics within the group comprising: inserting a classification identifier into a subject line of the message; inserting a classification identifier into a body of the message text; inserting a watermark in the body of the message form; and inserting security classification identification text at the start or end of the message form.