Version: (using KDE KDE 3.1) jabber protocol support presence signing, which is required by some client to encrypt/decrypt messages with gpg. Actually, kopete doesn't seem to support presence signing, and if an ecrypted message is send from a kopete client to a gabber client, gabber will not be able to decrypt it : the message is show encrypted ...
This is a wishlist item, no malfunction.
kopete doesn't implement correctly jabber protocol, so it can be considered as a malfunction. That's why i post it here.
It does not implement it incorrectly but is not implementing all features that the Jabber protocol offers. So this is a feature request (or wishlist item). I just put the comment there as Stephan Binner changed the severity of this item to "normal", whereas it should stay at "wishlist", as you originally submitted it. No fault on your side.
Message encryption for Jabber is described in http://www.xmpp.org/extensions/xep-0027.html, there is written: "[This method] does not include feature negotiation; instead, signed <presence/> is used as an indicator of support." So when you support XEP-0027, then it should be indicated with a signed presence.
Dear user, unfortunately Kopete is no longer maintained. Please migrate to another solution, e.g. for Jabber a possibility is Kaidan, for Matrix a candidate is NeoChat.