[Samba] Samba can't recongize machine account stored in LDAP

[DRVTiny]

It would be a nice and very comfortable for me to use Samba machine account in this (non-standart for Samba, bit classical for LDAP) format:

dn: cn=HOST$,o=MyORG,c=ru
objectClass: dhcpHost
objectClass: posixAccount
objectClass: sambaSamAccount
cn: HOST$
uid: HOST$
... (etc.)

I know that Samba uses filter (&(uid=ACCOUNT_NAME$)(objectClass=sambaSamAccount)) to find machine accounts in appropriate ldap subtree, so i was very confused, when discover that actually Samba can read ONLY accounts with "uid" in distinguished name, i.e.:

dn: uid=HOST$,o=MyORG,c=ru
objectClass: dhcpHost
objectClass: posixAccount
objectClass: sambaSamAccount
cn: HOST$
uid: HOST$
... (etc.)

But filter (&(uid=ACCOUNT_NAME$)(objectClass=sambaSamAccount)) equally corresponds to both records!
I dont understand, WHY Samba distinguish between dn: cn=HOST$,o=MyORG,c=ru and dn: uid=HOST$,o=MyORG,c=ru and refuses to work with "dn: cn=..."???