When a new virtual server is created, these two default entries seem to conflict with each other:
Contact email address: Unix user's mailbox
Create email address for unix user? No
If the default is to set the contact email address to the unix user's mailbox, then doesn't it need to be created (i.e. set to Yes)?
Also, since these two fields are directly related, I would suggest moving second one to be right under the first one on the form for continuity.