OT - EMEW (Enhanced Message-ID as Email Watermark) breaks pipermail threading

[Steve Freegard]

Hi Mark,

Mark Sapiro wrote:
> I notice a few frequent posters on this list, including Jules since
> late May, appear to receive list posts with Message-IDs munged with
> EMEW watermarks. Thus their replies to list posts have In-Reply-To:
> with the munged Message-ID which breaks threading in the pipermail
> archive at <http://lists.mailscanner.info/pipermail/mailscanner/>
> (every time Jules replies to a post, a new thread is started).
> 
> I am a Mailman developer and am concerned about what, if anything, I
> should do about this for the near term. My specific concerns are
> 
> 1. how wide spread is the use of EMEW likely to become.

Anyone using BarricadeMX can switch this on at any time.

> 2. How do I recognize the added data in the Message-Id? It looks like
> the regexp 'EMEW-[0-9A-Za-z]{6}[0-9a-f]{32}-' will work and removing
> the match will restore the original Message-ID (or at least the
> immediately prior Message-ID). Is that a good regexp, or is there a
> better one?

That regexp should work just fine.

However - you shouldn't modify Mailman in any way - there's obviously a 
bug that we need to fix.  We've simply not noticed it as I read the list 
using the GMane gateway and it threads just fine in Thunderbird.

> 3. Are there products other than BarricadeMX that are munging
> Message-IDs in other ways for similar reasons.

No to my knowledge.

> I haven't been able to find much on the web about this. I would
> appreciate any advice or additional information anyone can point me to.

We'll take this off-line and I'll contact you later once I've had a 
chance to speak to one of my colleagues.  We can then work out a fix and 
push it out to all the BarricadeMX users via yum.

Cheers,
Steve.