Exchange had it since 5.x (don't recollect if it existed in versions prior
to that). It's called "Single Instance Storage". The good news is it's not
an add-on - it's the default behavior. Only a single copy of a message
exists in one store, regardless of number of recipients.
Understanding Single Instance Message Storage
https://www.microsoft.com/technet/prodtechnol/exchange/guides/E2k3AdminGuide/8fa
39b5c-855e-45b6-956a-8a35ef59437a.mspx

Signature
Bharat Suneja
MCSE, MCT
www.zenprise.com
blog: www.suneja.com/blog
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> Back in Exchange 5.5 days when you would send an attachment to 10 people
> in
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> on called Shared Mail that will do the same thing. Is this possible in
> Exchange 2003??