This bug is detailed and fixed in the mentioned link to Mozilla's Bugzilla. I'm submitting a bug here because 1.7.5 is the only version of Mozilla currently in Portage, preventing me from running world updates. Reproducible: Always Steps to Reproduce: 1. Add a filter in Mozilla Mail using a custom header. (Like X-Spam-Flag for spamassassin) 2. Download mail. Actual Results: Nothing. That's the problem. ;) Expected Results: Filtered mail. Filtering does work when the filter is run manually.
Problem persists in 1.7.5-r1. All I would like to see, until the Mozilla project releases 1.8 as stable, is for 1.7.3 to be returned to Portage, since it functions properly in this regard.
Problem solved in 1.7.6-r1.