[tlug] Yet Another PGP question

[Ulrich Plate <plate@example.com>]

Spoke to Ryan Shaw off-list earlier who suggested I ask around the list
rather than just him. The thing is, I've imported everybody's public
keys (everybody who posted to TLUG over the past few weeks, that is).
Now, for most people who sign their messages I get GOOD signatures all
the time (the CAPS for good vs. bad is a Sylpheed phenomenon,
apologies), but two TLUG regulars (Ryan and Stewart Bouyer) show BAD
signatures in my mail client, as if they've had their messages edited
after signing them (that's one of the possible explanations, says the
GnuPG handbook). Even stranger than that is what happens to Chris
Mague's messages when they arrive in my inbox: I've imported three (3)
apparently valid public keys for his address, but I still get "no public
key to verify the signature". His are the only signatures this last
phenomenon occurred with so far.

Do any of the people who - unlike me - have been doing this for a while
know what's going on? Why are signatures BAD for me and not for others
(I assume other people get Ryan's et al. messages with good signatures)?
Why would three public keys still not be enough to verify a signature?

Cheers
Ulrich Plate

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