I need to journal all incoming and outgoing emails. Currently emails are relayed by Edge transport server to Exchange 2010 email store.
I'd like to stick a linux server in-line with an MTA. It would archive locally then relay to the Exchange server.
I'd like to ask how Open Source mail servers perform on email indexing and searches (of a monolithic mail store file).
Do any of the following mail servers allow you to index email messages?
Courier Mail Server
Meldware Mail Server
An email archive search GUI would also be nice for normal users. (not sysadmins using grep) Does such a thing exist? I know about Squirrelmail, but that is more web based email application, not a GUI to an email archive.