[Modus] Blacklisting via webmail

[Jon Saunders - SECPA]

Hello,   Sorry if this has been addresses in the list before, but is there a way for an end user to blacklist a whole domain from the webmail console?  When I put in [EMAIL PROTECTED], it gives the error "The address you have specified contains invalid characters"    I can, however, put in [EMAIL PROTECTED] in from the console.   Thanks Jon Saunders