Thunderbird maintains its own Certificate Manager. However, on Mac OS X, the Keychain is the system's way of managing certificates. This mismatch makes it a hassle to set up certificates. If you use Safari or Camino, when you go to the Thawte site to download a certificate, they store the certificate in the Keychain. At that point, you're stuck, because there is no way to get the certificate out of the keychain and into Thunderbird's Certificate Manager. If you want this to work, you must install and use Firefox to get the certificate into its Certificate Manager, and then you can extract it and move it to Thunderbird. If Thunderbird were to be able to use certificates from the Keychain for signing, this would alleviate this problem. (Except for Firefox users, but Firefox ought to use the Keychain as well.) (This is a subset of bug 106400, but that talks in general about using the keychain and doesn't mention certificates.)

This is also related, sorta, to bug 308863 (for Camino).

still valid in thunderbird 3?

(In reply to comment #2) > still valid in thunderbird 3? Yes. I'm temped to dup this to the PSM core bug

(In reply to comment #3) > (In reply to comment #2) > > still valid in thunderbird 3? > > Yes. I'm temped to dup this to the PSM core bug Or make this one depend on the the Core bug.

It might help if there was actually a Core bug on this