The times that I have seen this happen, it was an intermediate server that had the problem.  You will have to get copies of some of these messages will *ALL* the headers showing to track it down.  You have to look at the various Received headers to see the route the mail took.

At 1:44 PM +0100 3/31/06, Eggleston Scott wrote
> 
>Hi,
> 
>Can anyone help me with this problem.
> 
>Some of our users are experiencing problems with certain lists
>whereby old messages are periodically being resent to the list
>subscribers.
> 
>This is causing many problems as you can imagine especially if
>the communications are of high importance.
> 
>Is there any setting on the List Server that can be modified to prevent
>this ?
> 
>Any help appreciated.
> 
>Rgds
> 
> 
> 
>Scott Eggleston
>
>Senior Systems Engineer
>
>Systems & Applications
>
>NHS Connecting For Health (NPfIT)
>
>0113 397 3409
>
>[log in to unmask] <mailto:[log in to unmask]> 
>
>www.connectingforhealth.nhs.uk <http://www.cfh.nhs.uk/>
>
> 
>
> 
>
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-- 
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