[Dovecot] Multiple "mail" field in one LDAP account

[Proskurin Kirill]

Hello all!

#pkg_info | grep dovecot
dovecot-1.1.3_1
dovecot-managesieve-0.10.3
dovecot-sieve-1.1.5_1

Im trying to do this:
Im have a LDAP account with multiple "mail" field like this(many strings 
cuted):

dn: uid=k.proskurin,ou=Users,dc=Moscow,dc=CAS
uid: k.proskurin
userPassword: {CRYPT}$1$ETadxf6G$O2bNUQVSHxksUp08V/iY2.
mail: sysadmin at domain.off
mail: proskurin-kv at domain.off

My dovecot user "mail" as login:

user_filter = (&(objectClass=mailUser)(mail=%u))
pass_attrs = mail=user,userPassword=password
pass_filter = (&(objectClass=mailUser)(mail=%u))

All seems work well before im add second mail field in account.
In logs in see this:

----

Info: auth(default): client in: AUTH   1       PLAIN   service=imap 
secured lip=172.16.1.19 rip=172.16.1.19 lport=143       rport=64575 
resp=<hidden>

Info: auth(default): ldap(proskurin-kv at domain.off,172.16.1.19): pass 
search: base=dc=CAS scope=subtree 
filter=(&(objectClass=mailUser)(mail=proskurin-kv at domain.off)) 
fields=mail,userPassword
Info: auth(default): auth(proskurin-kv at domain.off,172.16.1.19): username 
changed proskurin-kv at domain.off -> sysadmin at domain.off

Info: auth(default): auth(sysadmin at domain.off,172.16.1.19): username 
changed sysadmin at domain.off -> proskurin-kv at domain.off

Info: auth(default): ldap(proskurin-kv at domain.off,172.16.1.19): result: 
userPassword(password)=<hidden> 
mail(user)=sysadmin at domain.off/proskurin-kv at domain.off

Info: auth(default): client out: OK    1       user=proskurin-kv at domain.off

Info: auth(default): master in: REQUEST        8       38582   1

Info: auth(default): master out: USER  8       proskurin-kv at domain.off 
uid=1002        gid=1002 
home=/var/spool/dovecot/domains/domain.off/proskurin-kv

Info: imap-login: Login: user=<proskurin-kv at domain.off>, method=PLAIN, 
rip=172.16.1.19, lip=172.16.1.19, secured

And in my Thunderbird then im log by sysadmin at domain.off in see 
proskurin-kv at domain.off mail.

----

Oh - what is happening? Why it is jump from one to another?
They have differnent login and same password. If it is possible to make 
this work well?

-- 
Best regards,
Proskurin Kirill