How do you get MailMax to allow literals such as:
postmaster@[24.248.49.26]

The domain needs to have an alias of its IP address.

1. Open the MailMax Admin.
2. Expand the 'Connection' (lightning bolt).
3. Click on 'Domains/Users'.
4. In the right pane, double click on the domain associated with the IP address.
5. Go to the 'Aliases' Tab.
6. Add the IP address (in this example: 24.248.49.26).
7. Click 'OK' to exit and save.

An alias of 24.248.49.26 will cause postmaster@24.248.49.26, to be accepted for delivery, an alias of [24.248.49.26], will cause postmaster@[24.248.49.26], to be accepted for delivery.