Mailbox Strainer is a Superkaramba widget that analyzes numerous IMAP mailboxes.
You can have several instances running simultaneously, each of which will check its collection of mailboxes. Mailbox Strainer allows you to use SpamAssassin to detect spam, or you can evaluate message headers modified by external spam checkers. Additionally, you can make SpamAssassin learn from particular IMAP or local folders. Configuration can be done either through the graphical interface or manually via a configuration file that comes with annotations.
Mailbox Strainer is written in Perl, and depending on which features you want to use, you will need to install a number of Perl modules. PerlQt is required for the configuration dialog, and all modules are readily available at cpan.org. Using the CPAN shell (perl -MCPAN -e shell) is a convenient way to resolve dependencies automatically. To determine which modules are missing on your system, run module-test.pl. However, the local mail capabilities are those of the Email::Folder::* modules, so they should be able to handle mbox and maildir.
Unfortunately, using the spam detection with local mbox folders is strongly discouraged as it is likely to destroy your emails. Therefore, spam checking is currently disabled for local mailboxes. Despite this, you can enable spam checking by changing lines 975, 998, and 1081 in perl/mailbox-strainer.pl. Simply remove "0 &&" from each of those lines to enable spam checking.
A few words about password storage: The configuration dialog stores encrypted passwords (of length at least 8) in the configuration file. This is meant to protect against accidentally displaying the configuration file, but nothing else. You should consider this as a parody of proper encryption since even the 'secret' key can be found in the Perl scripts.
To use Mailbox Strainer, you'll need to have SuperKaramba installed on your system. The recent release has dropped the Perl DCOP module and uses a system call instead.
Version 0.91: N/A