On 2006-07-12 at 12:19-04 Barry Warsaw barry@python.org wrote:

On Jul 12, 2006, at 11:54 AM, James Ralston wrote:

...

As a follow-up to the Sender header discussion back on 2006-04/05...

On 2006-06-17, we disabled Sender header rewriting at our site, using the attached patch.

Since then, we've received no complaints whatsoever from our users about bounces not being caught, and the complaints about recipients using Outlook seeing "bounce" addresses have ceased.

Based on our experiences, I'd strongly recommend that this patch be applied to the official Mailman distribution.

Thanks for the feedback James. Have you seen any problems with processing legitimate bounces to addresses that don't exist?

Here's our count of bounces without discernable addresses so far for the year:

Month     count
---------------
2006-01      10
2006-02      32
2006-03      36
2006-04      32
2006-05      16
2006-06      12
2006-07       6

I'd like to see the data through, say, September before drawing any firm conclusions, but we definitely have *not* seen any sharp increase in the number of bounces without discernable addresses.

As an aside, we average about 3,259 bounces per month across all lists, so having only (e.g.) 12 unrecognized bounces is actually a very impressive number (about 0.37%).

James