[SIEVE] pipe :copy to external program with arguments

Hi all,

quick questions about sieve pipe: I want to pipe spam messages to an external program with additional parameters

my spamlearn.sieve script:

require ["vnd.dovecot.pipe", "copy", "imapsieve"]; pipe :copy "mybin" ["-h 127.0.0.1:44444" , "markspam"];

I also tried: pipe :copy "mybin" ["-h 127.0.0.1:44444 markspam"]; pipe :copy "mybin" ["-h 127.0.0.1:44444"] ["markspam"]; pipe :copy :args ["-h 127.0.0.1:44444 markspam"] "mybin" ;

It never executes correct, it always ends with: Error: sieve: Execution of script /my/path/to/spamlearn.sieve failed

So whats the correct syntax ?

What works is a single argument: pipe :copy "myscript" ["markspam"];

Dovecot Version 2.3.2.1