[Dovecot] Pigeonhole sieve re-filter extension?

Dear Stephan Bosch, dear Dovecot community,

"sieve-filter" re-filtering of existing mails is already a great progress for everyone using sieve! But as far as I know this functionality is just accessible by the server administrator.

In the meanwhile everyone knows the comfort of re-executing filter scripts on his own existing mailboxes - triggered by himself!

This service is already very widespread. Examples are MUA's like Outlook or Thunderbird which provide this service just on the client side. Or almost every web-mail provider offers this.

Is there already an managesieve protocol extension that allows client triggered server side re-filtering?

If not, maybe you could design a RFC for this?

What do you think?

Best regards.

T.B.