The requirement by Plesk to have a "Catch to" address defined without a "none" option is a serious problem. It means that every single piece of malformed SPAM garbage will be accepted, spooled and delievered somewhere. This means that Spammers that check for valid accounts by brute force attacks (trying one account name at a time) will find a bonanza as every address will return a positive result, meaning that even MORE **** will be targeted towards those servers in the future. Multiply that by several hundred domains on a Plesk server and you have a major problem. This becomes even worse when you factor in the fact that Plesk doesn't support Mailbox Quotas. However, MailEnable does all these things and more. I would HIGHLY suggest that even before 7.0 is release that 6.5 have a patch released that adds the following features: 1. Mailbox Quota Size 2. Ability to define the Postmaster and Abuse addresses 3. Ability to select a "None" option for the "Catch To" address that gives a 550 User Unknown error for unknown users. These would be trivial to add.