How does one select the Archive folder in Mail using Applescript?

[amityweb]

Does anyone know how to select the Mail Archive folder in Mail using Applescript?

This code does not work, BUT if I change Archive to any other folder it works fine. It is only the Archive folder which is not working!

tell application "Mail"
    set selected mailboxes of message viewer 1 to {mailbox "Archive"} of account "My Email"
end tell

Thanks