[Dovecot] Problem with master user

[Jakub Krzyżewski]

Hello.

I have problem as below:

Nov  8 10:41:52 store1 dovecot: auth: Debug: 
auth(master at example.com,::1,master,</qEuMafqyAAAAAAAAAAAAAAAAAAAAAAB>): 
Master user lookup for login: jkrzyz at example.com
Nov  8 10:41:52 store1 dovecot: auth: Debug: 
passwd-file(master at example.com,::1,master,</qEuMafqyAAAAAAAAAAAAAAAAAAAAAAB>): 
lookup: user=master at example.com file=/etc/dovecot/master-use
rs
Nov  8 10:41:52 store1 dovecot: auth: Debug: 
password(master at example.com,::1,master,</qEuMafqyAAAAAAAAAAAAAAAAAAAAAAB>): 
Generating DIGEST-MD5 from user 'master', password 'test'
Nov  8 10:41:52 store1 dovecot: auth: 
passdb(master at example.com,::1,master,</qEuMafqyAAAAAAAAAAAAAAAAAAAAAAB>): Master 
user logging in as jkrzyz at example.com
Nov  8 10:41:52 store1 dovecot: auth: Debug: 
ldap(jkrzyz at example.com,::1,</qEuMafqyAAAAAAAAAAAAAAAAAAAAAAB>): pass 
search: base=dc=example,dc=com scope=subtree filter=(&(locMailActive=TRUE)(|
(uid=jkrzyz at example.com)(uid=jkrzyz)(mailRoutingAddress=jkrzyz at example.com))) 
fields=mailRoutingAddress,userPassword
Nov  8 10:41:52 store1 dovecot: auth: Debug: 
ldap(jkrzyz at example.com,::1,</qEuMafqyAAAAAAAAAAAAAAAAAAAAAAB>): result: 
mailRoutingAddress=jkrzyz at example.com userPassword=test2
Nov  8 10:41:52 store1 dovecot: auth: Debug: 
password(jkrzyz at example.com,::1,</qEuMafqyAAAAAAAAAAAAAAAAAAAAAAB>): 
Generating DIGEST-MD5 from user 'master', password 'test2'
Nov  8 10:41:52 store1 dovecot: auth: Debug: 
password(jkrzyz at example.com,::1,</qEuMafqyAAAAAAAAAAAAAAAAAAAAAAB>): 
Credentials: d64221d543d7c9a809c7d6e424d87be8
Nov  8 10:41:52 store1 dovecot: auth: 
digest-md5(jkrzyz at example.com,::1,</qEuMafqyAAAAAAAAAAAAAAAAAAAAAAB>): 
password mismatch

As you can see, password is check against user passdb and not 
passwd-file, where master's password is stored.
Test is password of master user, test2 is password of jkrzyz
Setting pass=yes or no makes no difference.
What is wrong with my config?

dovecot --version
2.1.7

dovecot.conf snippet:

passdb {
   args = scheme=PLAIN /etc/dovecot/master-users
   driver = passwd-file
   master = yes
   pass = yes
}
passdb {
   args = /etc/dovecot/dovecot-ldap.conf.ext
   driver = ldap
}
userdb {
   args = /etc/dovecot/dovecot-ldap.conf.ext
   driver = ldap
}

/etc/dovecot/master-users:

master:{PLAIN}test
master at example.com:{PLAIN}test