pdfDeliver is a WIN32 dll library that allows to easily generate secure PDF files from plain ones. In the conversion process it is possible to specify the passwords and permissions, resulting in a personalized PDF.
The dynamically created file is in Acrobat 6.0 format and preserves all the features of the original file (pages, images, fonts, annotations, interactive features, etc.).
OK, so you want to stamp your document. Maybe you need to give reviewers some advice about the document's status or sensitivity. This tip from author Ted Padova demonstrates how to add stamps with the Stamp Tool along with related comments.