duplicate suppression, sieve, loops, redirect and lost email

[Kevin P. Fleming]

Ken Murchison wrote:
> Forget about duplicate suppression, even if it was turned off, the user
> has created a loop in which the message will not get filed/kept.  Every
> time the message hits the sieve script, it is going to be redirected,
> until something breaks the loop.
> 

Right, but is this even the mailstore's responsibility at all? Are there 
any other mailstores that do this? AFAIK, all decent MTAs already handle 
finding and stopping mail loops by counting received headers, so the 
loop would get stopped.

Granted, the user needs to be educated as to what they should/shouldn't 
do with their sieve scripts... but going by the other responses in this 
thread, if the sieve engine could keep track of what message ids it had 
previously redirected, the transmogrification of "redirect" into "keep" 
would be pretty straightforward.