We are currently hosting several e-commerce vendors. We are looking for a way to provide them with email clustering or some other way of safe email storage. We need to be able to provide the customer with access to his email account, even if a single server is down. What server platform and software can we use to do this. We are currently using IMAIL. I do not believe that we can do it using IMAIL. I was thinking of Linux possibly. We also need the system to provide very good anti-spam and anti-virus capabilities.