Hello, Mr. Rod Whiteley from the MozillaZine Thunderbird Forums gave me the hint to bring up my questions in this newsgroup.
We experienced, that Tb uses the algorithm RC2 if you send a S/MIME encrypted eMail to KMail. KMail (and Claws Mail) use gpgsm to handle the S/MIME mails. In gpgsm the RC2 algorithm is not implemented for patent reasons. The behavior of Tb arises from its handling of the S/MIME capabilities. KMail requests an algorithm (I think AES), which Tb does not support. In this case Tb seems to fall back to RC2. Tb uses 3DES (which it normally does - communicating with other Tb), if you import the certificate manually. As soon as you reply to a KMail eMail by using the "Reply" - button it uses RC2 again. Are there about:config entries for at least one of the following proposed solutions: a) Disable RC2 in Tb. b) Set the default fallback to 3DES. c) Switch on AES. d) disable interpreting of "smimecapabilities" The original thread is at http://forums.mozillazine.org/viewtopic.php?p=2858116#2858116 Interesting readings: http://kb.mozillazine.org/Message_security and http://www.mozilla.org/projects/security/pki/nss/nss-3.11/nss-3.11-algorithms.html In http://www.gossamer-threads.com/lists/gnupg/devel/40286 and http://www.gossamer-threads.com/lists/gnupg/devel/40396 "wk at gnupg" stated, that it is not a problem of gpgsm. **_He thinks, that this is a bug in Tb, which should be fixed._** The keys mentioned by "patrick at mozilla-enigmail" are set to false (by default). Thank you very much for your help, wurstsemmel _______________________________________________ dev-tech-crypto mailing list dev-tech-crypto@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-tech-crypto
