Configuring iPrint Appliance for email printing fails authentication

Within the iPrint Appliance Management Console, there is an option to configure the Appliance to connect to an email system using an email account user name and password.  The user name and password fail with the following error:

An error has occurred. See the server logs for more information.

Use the full email address of the user in the "Account Username" field.  For example, use myaccount@gmail.com instead of myaccount.

Depending on the email system, an account name (SMTP) may be required, or for other email systems the full email address (ESMTP) may be required.  For example, GMAIL requires the ESMTP method (full email address) when authenticating. 

A LAN trace will show that after the Appliance sends the user/password values, a syntax error in parameters or arguments (501) error is returned from the ESMTP server.  This error indicates that only the user name was sent, instead of the required full email address.

The iprintmobile0.log shows:

[DATE] com.novell.service.iPrint.mobile.notification.email.EmailNotificationService init
SEVERE: Failed to initialize
javax.mail.AuthenticationFailedException: 501 Authentication failed

    at com.sun.mail.smtp.SMTPTransport$Authenticator.authenticate(SMTPTransport.java:826)
    at com.sun.mail.smtp.SMTPTransport.authenticate(SMTPTransport.java:761)
    at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:685)
    at javax.mail.Service.connect(Service.java:295)
    at javax.mail.Service.connect(Service.java:176)
    at com.novell.service.iPrint.mobile.notification.email.EmailNotificationService.init(EmailNotificationService.java:112)
    at com.novell.service.iPrint.mobile.notification.email.EmailNotificationService.processNotifications(EmailNotificationService.java:333)
    at com.novell.service.iPrint.mobile.notification.email.EmailNotificationService.run(EmailNotificationService.java:373)
    at java.lang.Thread.run(Thread.java:798)

After changing the Account name to the full email address, there are no errors and it works.