The reviewer request emails don't have the options to change or add email addresses because we're concerned that Editors or Section Editors might intercept reviewer access information and interfere in the review process.
Are you using SMTP mail? If not, try configuring and using it in your config.inc.php. Otherwise, please see if you can narrow down the situations in which the mail originates from the anonymous account.
Open Journal Systems Team
Don't miss the First International PKP Scholarly Publishing Conference
July 11 - 13, 2007, Vancouver, BC, Canada