It only works without :addresses for me And even when getting this on confirmation the logs:
Feb 24 09:03:52 localhost dovecot: lmtp(7895, a...@dum.li): yeIlOfjN61TXHgAA0J78UA: sieve: msgid=<451bb443b8ad815c205a2cce07ac31aec0727c47@vm-atmail7>: sent vacation response to <a...@dum.li> It wasn't working. This did the trick on CentOS 7 though: alternatives --set mta /usr/sbin/sendmail.exim Cheers
