[5.6-current] doveadm doesn't support SHA256, SHA512?

[Neddy Nguyen]

  Hi, I've installed 5.6 snapshot (Nov 18) on my laptop, and installed dovecot 
package. But failed when setting up password crypt scheme:
 
# doveadm pw -s SHA512-CRYPT -p 123456
doveadm(root): Fatal: Unknown scheme: SHA512-CRYPT
# doveadm pw -s SHA256-CRYPT -p 123456
doveadm(root): Fatal: Unknown scheme: SHA256-CRYPT
 
Only MD5 and Flowfish work:
 
# doveadm pw -s MD5-CRYPT -p 123456
{MD5-CRYPT}$1$LH6gX62O$8WYWxZ6JvBFbY04c/g0Bb1
# doveadm pw -s BLF-CRYPT -p 123456
{BLF-CRYPT}$2a$05$s/mtTvrm2JaI4brMU.fIxujhymqiNsMpPdMksCcjV5ECOjNotksj.
 
# dovecot --version
2.2.15
# uname -a
OpenBSD vaio.test.test 5.6 GENERIC.MP#571 amd64
 
Does anybody have idea about this issue? 
Thanks.
~Nedd