Preventing multiple signatures in email conversation?

Julian Field MailScanner at
Mon Apr 27 19:39:10 IST 2009

On 27/04/2009 19:09, Chris Barber wrote:
>> I think this has already been mentioned in this thread. But...
>> With an HTML signature, it's easy as you can insert some hidden text in
>> the sig that doesn't appear in the viewed result, and use that as an
>> identifier to say "Here is the sig, don't add another one".
>> But in a plain text message, it's a lot harder as there is no way of
>> putting in hidden text, and once the message has been badly quoted by
>> some mail client when the reply was done, you can't reliably
>> automatically find the original signature in it.
>> When you're passing through multiple MailScanner servers in the same
>> organisation, you can do it with a header. But you can't trust the
>> contents of any header once you've been outside your organisation, as
>> many environments throw away most headers, particularly when the
> message
>> has been replied to.
>> In the cases of multiple MailScanner servers, and HTML signatures, I
> can
>> and already have solved the problem. There just isn't a neat way of
>> doing it for plain text signatures, sorry.
>> If you have any stunning ideas, then let me know :-)
>> Jules
> Jules,
> > From your first paragraph there, are you referring to the "Allow
> Multiple HTML Signatures" setting?
>   I tried that setting using an image
> tag without a src and it doesn't work for me because some email client
> change the<img>  tag that is missing the src to an error message and
> thus MailScanner won't see it when it comes back in.
You could put in the src as the same URL as the Web Bug Replacement in 
MailScanner.conf. They won't be able to see that, but it will make the 
img tag correct. And that URL will always be accessible, and widely 
available as it's hosted by an anycast network of servers scattered 
around the world.
> > From your reply above it sound like there is another way to get this
> done?
Not particularly, should there be another way?


Julian Field MEng CITP CEng
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MailScanner customisation, or any advanced system administration help?
Contact me at Jules at Jules.FM

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