There appears to be some inconsistency when adding contacts to a specific Telepathy account through Kopete - look at createNewContact in telepathyprotocol.cpp and ui/telepathyaddcontactpage.cpp. How is it decided which account a contact is added to? (I'm filing this bug report so I don't forget to look into this bug as I don't have time right now...)
I believe this was resolved when oggis rewrote/updated large chunks of this codebase.