[Dovecot] Sieve regex never matches

[frank.kintrup at fkware.de]

Hi,

I found the following code on the net which should redirect all mails
to another address depending on the time of day (useful for forwarding
mails to work):

 require ["regex"];
 if allof (header :regex "date" "(08|09|10|11|12|13|14|15|16|17):..:..",
           not header :regex "date" "(sat|sun)") {
     redirect "address at work>";
     keep;
 }

To check and test I simplified the regex to match all mails within a
certain hour:

 require ["regex"];
 if header :regex "date" "20:..:.." {
     redirect "user at domain";
     keep;
 }

 
Both scripts compile fine, but their regex never match. Has anyone
an idea why? I'm using Dovecot 1.0.0 on Debian Etch stable.

Frank