PGP 6.5.3 reports bad signature on GnuPG signed files/mails

[Len Sassaman]

On Tue, 26 Jun 2001, Timo Schulz wrote:

> 5.5) Why is PGP 5.x not able to verify my messages?
>
>     PGP 5.x does not accept V4 signatures for data material but OpenPGP
>     requests generation of V4 signatures for all kind of data, that's why
>     GnuPG defaults to them.  Use the option "--force-v3-sigs" to generate
>     V3 signatures for data.
>
>
> IMO it's also for PGP 6.x and 7.x.

6.x and 7.x generate only v3 signatures on non-key material. 7.x can
verify v4 signatures on non-key material.