I’ve just set up a customer (IMAP account, running Mail.app on a MacBook Pro running 10.5.5) with SpamSieve 2.7.3, but I cannot get SpamSieve to route “Train as Spam” messages to the user’s IMAP-based spam folder. It instead creates a local folder of the same name, despite repeated use of the “Change Settings” process that normally would clear this sort of thing up.
The SpamSieve rule is set to direct auto-processed mail into an IMAP spam folder – that much is working properly.
I also tried quitting out of Mail.app and SpamSieve and then ditching the com.c-command.SpamSieve.plist file (starting fresh), hoping there was something mangled in there, but it didn’t make any difference.
The only thing remotely different about this user is he uses the Letterbox three-pane plugin for Mail, but I can’t imagine why that would affect SpamSieve’s routing?