There are two basic problems with digitally signed documents. If it were a paper document without acknowledgement wording, you could use a rubber stamp to put the acknowledgement wording at the end, but altering a digital document in any way would invalidate the signature, so you can't add the acknowledgement to the existing document.
Also, if it were a paper document, you could staple a loose acknowledgement to it, but you can't staple computer files together. So the specimen acknowledgement on my web page is my idea of how to describe a signed computer file well enough that people can tell which computer file the acknowledgement goes with. |
