My company currently has several active directory forests with no relationship to each other. Some of these sites are running Exchange and the largest is running Domino. Discussions are now happening on how to migrate everyone to Exchange.
Due to the fact we are still under multiple forests and don't have a healthy active directory I think it's worth pushing Zimbra as deploying Exchange could be very costly and take years to deploy based on our current situation.
I would like to understand the necessary hardware requirements for a full enterprise Zimbra solution. It's my understanding Zimbra can support all AD forests and multiple domains within one server.