We need to set up a multi tenant system for our clients so that they can have sites hosted on one server and and email on another. We want the setup to be automated so that virtual host information is added automatically upon account initiation. We also want to set up a separate email server that can host the clients' emails for multiple domains.
We have the application working in PHP, so will need help setting up the email server and creating shell scripts that we can invoke with PHP to create and manage both the domain and email accounts.
We've identified Zimbra as a good mail server option, but are open to better alternatives.
We have left budget $5/$5000 so that you can bid based on the time you expect to spend on this task.