I am looking for a good standards-based component for x509 certified digital sign documents. I do not see any native component for this. Activex components only.
You can use OpenSSL for this.
look here: delphiopenssl
The problem with yourself is that you do not have a third party that is an independent verification of the validity of the certificate.
This is trust, and therefore companies such as VeriSign and Comodo make a lot of money.
Check out A secure black box from Eldos , which I used in my applications to “sign” files.