It's is infinitely more accurate and far easier to set up message filters on header fields like X-Loop: X-Been-There: Sender: than it is to try and filter based upon To: and Cc: fields when dealing with mailing lists. 90% of my old filters where based upon these fields and it would properly sort my mail (including things like if I got two copies of an email because it was being sent to both myself and a list I was subscribed to, the copy that came directly to me would fall into my Inbox and the copy the list sent me would go into my list folder), but during the conversion from Netscape 4.x filters to Mozilla filters, all of the custom header information was lost and the resulting filters were all non-functional.

*** This bug has been marked as a duplicate of 16902 ***

Marking verified as a duplicate.