[Dovecot] sieve problem after upgrade to 2.1.12

Hi,

I have a sieve filter for a mailbox with amavisd-admin mails.

if header :regex "Subject" "^INVALID HEADER" { fileinto "INVALID HEADER"; }

After the upgrade to dovecot 2.1.12 this filter doesn't work for some (16) messages with this subject. For 424 messages it worked correct.

Any ideas where to look?

Bye Daniel