Why does PGP 2.x complain about checking signatures every so often?
Version 2.3a introduced the “pkcs_compat” option, allowing the format of signatures to change slightly to make them more compatible with industry standards. MIT PGP, because it uses the RSAREF library, is unable to understand the old signature format, so it therefore ignores the signature and warns you that it is doing so. This problem comes up mostly with old key signatures. If your key contains such old signatures, try to get those people who signed your key to resign it with a newer version of PGP. If an old signature is still vitally important to check, get a non-MIT version of PGP to check it with, such as ViaCrypt’s.
