We do not allow you to create Domain Administrator Accounts in SmarterMail.
Grey Listing can not be changed through a Domain Administrator as Anti-Spam (including Grey Listing) and Anti-Virus is handled by our Gateway Mail Servers.
The Gateway Mail Server uses Declude, Commtouch, RBL's lists for Spam and AVG for Anti-Virus. Grey Listing is used but only if the email receives a spam score of 10 (SPAM-LOW) or higher.
This is done as Grey Listing can add a delay of 5 minutes or more to the delivery of an email, by only using Grey Listing on emails detected of being Spam it means that you still have the benefits of Grey Listing without the delays that it can impose.
If you wish to check the storage space of your mailbox you need to login to your Webmail Account for the mailbox and then go to 'Reports -> My Reports -> Disk Usage'