[Dovecot] Sieve notify error?

Hi, I am playing with Sieve, everything is working nice except notify method. Source script looks like this (generated with avelsieve):

require ["fileinto","envelope","reject","vacation","imapflags","relational","compara tor-i;ascii-numeric","notify"]; if #hashed-avelsieve-source true { keep; notify :method "mailto" :options "xxx@xxx.xx" :low :message "Nova zpráva.";

}

but with no success. Message is delivered fine, but notification is not sent. Deliver logs only this:

deliver(xxx@xxx.xx): Apr 28 20:05:23 Info: sieve runtime error: Notify: Generic Error

Thanks for any ideas how to get this working.

Láďa