EM12c: How to fix BI Publisher 11.1.1.6.0 report error that shows invalid username/password error?

Issue: With EM12cR2, 11.1.1.6.0 BI Publisher is installed and integrated successfully. However, on accessing any report via BI Publisher as sysman user. It shows following error:

Parameter name: targettype weblogic.common.resourcepool.ResourceDeadException: 0: Could not connect to 'oracle.jdbc.OracleDriver'. The returned message is: ORA-01017: invalid username/password; logon denied It is likely that the login or password is not valid. It is also possible that something else is invalid in the configuration or that the database is not available.

Following error is seen in BIP managed server's log file(BIP.out):
2013-Jan-31 12:26:28EMReposAuthenticatorHelper: Following SQLException occurred.
SQLException code=28009 error msg: ORA-28009: connection as SYS should be as SYSDBA or SYSOPER

Problem verification:
When trying to connect EM repository as mgmt_view user via sqlplus. It works fine.

%$ORACLE_HOME/bin/sqlplus mgmt_view/<passwd>@<emrep>
SQL*Plus: Release 11.2.0.3.0 Production on Fri Feb 1 10:06:48 2013
Copyright (c) 1982, 2011, Oracle.  All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
SQL> Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options


Apparently, at some point along with other EM repos users, mgmt_view user password got modified using sqlplus. Which is the not supported way of modifying mgmt_view user passwd.

Action:
On OMS machine, execute the following command:
% $ORACLE_HOME/bin/emctl config oms -change_view_user_pwd -sysman_pwd <sysman_pwd> -user_pwd <user_pwd>
Oracle Enterprise Manager Cloud Control 12c Release 2
Copyright (c) 1996, 2012 Oracle Corporation.  All rights reserved.
Successfully changed password. You must restart the BI Publisher Enterprise Managed Server in order for BI Publisher to function correctly.


Restart the BIP server using weblogic console and restart oms using emctl commands:
% $ORACLE_HOME/bin/emctl stop oms

% $ORACLE_HOME/bin/emctl start oms