What das "err 221" mean?

Dear razor users,

since three month I'm using razor together with amavis to identify spam. To contribute to this project and make the spam detection better I want to report the mails which got not detected by using the razor-report command line utility.
For informal reasons I run the report in verbose mode (-d switch). For some emails the razor server reports " report: mail 1, 0: Server accepted report" which looks to me that the email was successfully reported as spam.
But in 99% of the cases I get the error 221:

mail 1.0, eng 8: got err 221 for query:
 HASH - HASH(0x1285ba8),3 keys
    a => r
    e => 8
    s => ARRAY - ARRAY(0x11a9608),3 items
        Ddy6Pd75oDcA
        WrIEdpzWoDcA
        t7JW3jJLoDcA

So I suppose that the email is not reported nor recognized as spam.
Is that right?
What does err 221 mean and why does it appear?
What can I do to successfully report the email?

Cheers.

David