User-Agent: Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.6) Gecko/20040206 Firefox/0.8 Feature request: Not convinced Bayesian filtration is sufficient. Some spam contains nothing but linked images and random words/garbage words, and I can't see how a Bayesian filter can catch them. Options to run SpamAssassin tests (as previously available through SAproxy, now commercial software) would be an excellent addition. Reproducible: Always Steps to Reproduce: 1. 2. 3.
The fix for bug 290237 has added a feature in TB to honor junk-detection headers added by the ISP; the built-in support is for SpamAssassin. However, I don't think it's appropriate to add a capability to actually run SA from TB; as stated in comment 0, this can be done via a proxy, and that should be the extent of the interface -- just as is done now for virus detection.
Clearly it's already thought of as appropriate to have spam filtration as part of the e-mail client, so why not make it better? Furthermore, many people have terrible ISPs without SpamAssassin. Running a proxy may be a solution for you or me, but most end users have know idea what that means, or how to begin doing it.
This feature was (in another form) worked into Thunderbird 1.5, see bug 224318. (This comment hopefully helps people who search bugzilla for SA integration.)
Another solution for folks looking for a subset of SA's features is the Thunderbird Extension for Sender Verification - http://taubz.for.net/code/spf/ . The extension uses Sender Policy Framework (SPF) (in a nonstandard way), DomainKeys (DK), and the phishing database of MailPolice.