Using key made with pgp 2.x?

Stainless Steel Rat ratinox at
Thu Dec 17 11:51:27 CET 1998

Hash: SHA1

"EK" == Erno Kuusela <erno at> writes:

EK> I have been using PGP 2.6.3ia, but it seems it does not grok
EK> the more modern public keys (I am seeing a lot if "Unsupported packet
EK> format - you need a newer version of PGP for this file" messages).

That is correct.  PGP 5 deprecated RSA keys in favor of Diffie-Hellman (DH)
keys, and PGP 6 does not grok RSA at all.  RSA is patented, and has an
extremely restrictive use license, whereas the DH patent has expired and is
now public domain.  Likewise, PGP 5 deprecates IDEA in favor of 3DES.

GnuPG, being free software, cannot use RSA or IDEA because of patent and
license restrictions[1].  So it is probably time for you to bite the bullet
and generate a DH key for yourself.

[1] There are RSA and IDEA modules for GnuPG, but the former cannot be used
in the US, and neither are free which is why they are not distributed with
Version: GnuPG v0.4.5 (GNU/Linux)
Comment: For info finger gcrypt at


Rat <ratinox at>    \ When not in use, Happy Fun Ball should be
PGP Key: at a key server near you! \ returned to its special container and
GPG Key: same as my PGP 5 (DH) key  \ kept under refrigeration.

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