Problem interoperating with PGP Univeral?

[David Shaw]

On Sat, Mar 31, 2007 at 11:29:54PM +0200, Patrick Brunschwig wrote:
> Blumenthal, Uri wrote:
> > I am trying to get cleartext-signed PGP/MIME messages produced by PGP
> > Universal 2.5.3, verified by email clients (Thunderbird-1.5.0.10 +
> > Enigmail-0.94.2 + GPG-1.4.7).
> > 
> > So far my experience is:
> > 
> > - Pure plaintext (neither PGP/MIME nor PGP/Partitioned) messages are
> > verified OK.
> > 
> > - PGP/MIME encrypted and signed messages are decrypted and verified OK.
> > 
> > - PGP/MIME or PGP/Partitioned messages (HTML body and/or attachments)
> > fail signature verification, with error message from GPG:
> > 
> >   Cleartext signature without data
> > 
> > I've submitted help request to Enigmail list, but perhaps somebody here
> > can advise me regarding this issue? Maybe there are settings at PGP
> > Universal that should be changed to make its output "friendlier"? Or
> > maybe there are GPG setting that would allow verification of those
> > emails? 
> > 
> > I'll be grateful for any help!
> > 
> > Thank you!
> 
> I can provide some more details on this. GnuPG 1.4.7 returns with this
> error message "gpg: can't handle this ambiguous signature data".
> 
> This is the detached signature that comes with such a message:
> 
> -----BEGIN PGP SIGNATURE-----
> Version: PGP Universal 2.5.3
> 
> qANQR1DEDQMBAhH9zteyosL+MwHCPwMFAUYL2iX9zteyosL+MxECC8QAnRhWP2Sx
> Ex7VcRL+wBVB2C7lksYAAKCYHvRP7E8vA5jKNgigU0o4kbFn4w==
> =lOCI
> -----END PGP SIGNATURE-----

That's just a regular signature.  How does Enigmail call GPG to do the
verification?

David