After Database Vault installiation cannot Create/Alter user

Hi experts,
I have installed Oracle Database 10.2.0.3 and Oracle Database Vault 10.2.0.3 and installation went successfully. Right after I'm connecting to DB with Vault Account Manager User (I gave it DBVmanager name) and trying to execute this:

SQL> connect DBVmanager
Enter password: ************
Connected.

SQL> alter user "HR" account lock;
alter user "HR" account lock
*
ERROR at line 1:
ORA-01031: insufficient privileges

DBVmanager has these roles:

SQL> select * from dba_role_privs where grantee like 'DBVMANAGER';

GRANTEE GRANTED_ROLE ADM DEF

---

------------------------------ --- ---
DBVMANAGER DV_ACCTMGR YES YES
DBVMANAGER CONNECT NO YES

I know, that DV_ACCTMGR purpose is to allow create/alter new user. Why I’m not allowed to do that? How this should be fixed?