PGP5 and v4 GPG keys

[David Shaw]

On Wed, Oct 27, 2004 at 06:18:06PM -0400, Hasnain Mujtaba wrote:
> Hello,
> 
> I read in an old GPG archives message (dated 2000) that PGP5.x cannot
> encrypt a message using a GPG v4 public key. RFC2440 says something
> about PGP5 not being able to properly encrypt to RSA v4 keys. Are these
> two issues related?
> 
> Can anyone shed light on this problem. Why is PGP 5 picky about RSA v4
> keys? 

PGP 5 predates OpenPGP, and as such is not OpenPGP compatible.  GnuPG
is OpenPGP.  It's a miracle they communicate at all.

David