[Enigmail] PGP indicates enigmail signed messages are invalid

[Moonchild]

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Hash: SHA1

Hey folks,

I've run into a rather peculiar problem using enigmail. I've been
looking at upgrading my mail client since my current one (Turnpike)
isn't really supported anymore by the developers. Turnpike uses
integrated PGP 6.5 to handle encrypted and signed messages. This setup
hasn't given any issues with decrypting and verifying signed messages
from anyone (including people using, for example, MUTT+OpenPGP and/or
GNUPG).

I've installed and tested (the current version of) enigmail on
thunderbird 2.0.0.20, and ran into the following situation:
- - Any message sent with a PGP signature using enigmail is flagged by my
Turnpike/PGP as "invalid signature, message does not match signature"
- - The signatures themselves check out fine (all data of the sender is
correct)
- - There is no problem decrypting messages with PGP either

* I've had my fiend with MUTT/OpenPGP check a message and he says the
signature checks out fine for the message.
* Thunderbird itself says the signature is fine (also when sending
through an external route the same as when checking with Turnpike).
* This problem occurs regardless of what service I use to send/receive
mail (so it doesn't seem to be a server/MTA problem).

Is this a known issue with PGP? I thought it used the exact same standard...
Is there a way around this? I would like to be able to sign my e-mails
in the most compatible way possible so people with older PGP versions
will also be able to verify my messages haven't been altered. I rely on
verifiable digital signatures for work. I've tried using PGP/MIME or
"regular" signing already. I can't get it to verify at all.
As said: any other mail signed with PGP and OpenPGP seems to be fine, so
I'm a bit at a loss where the problem lies.

Thanks in advance,

  MC


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