Merging 2 Exchange 2003 Orgs into one

[KCompateso]

Does anyone know of a tool that merges (migrates) 2 separate Exchange 2003 Organizations onto one? My company recently merged with another and we want to merge the other company's Exchange 2003 Org within our own.

-Kevin, "If it wasn't for bad luck, I'd have no luck at all

 

[Zelandakh]

Personally I prefer the simple options...

Pick the smaller one and exmerge all mailboxes.
Take the big one, create all user accounts (there are tools around to export from smaller and import to bigger), update the recipient policy if you need to do so to allow inbound emails to old domain.
Sort out bridgeheading to allow bigger domain to receive emails to smaller domain.