High CPU Utilization after start OMS

Grid Control 10.2.0.2
Repository Database 10.1.0.4
Windows 2003 R2 SP2

After new installation of 10g Grid Control on this server, CPU keeps running 100%. Every time I stop OMS using "opmnctl stopall", CPU utilization falls back to normal.
Every time "opmnctl startall" is issued, CPU utilization go up to 100% again and never fall down.

After checking Task Manager, I found out oracle.exe occupies near 99% of CPU utilization.
On windows platform, there is only one oracle master process, and it is divided into several oracle threads.
In order to check CPU utilization for each thread, "Performance Monitor" is the best solutoin. "Diagnosing High CPU Utilization on NT" (metalink note: 116236.1) gives a detailed explanation.

After some check on dynamic performance views, using

SELECT ss.sid,se.command,ss.value CPU ,se.username,se.program
FROM v$sesstat ss, v$session se
WHERE ss.statistic# IN
(SELECT statistic#
FROM v$statname
WHERE name = 'CPU used by this session')
AND se.sid=ss.sid
ORDER BY ss.sid;

I'm still unable to identify the problem, even though I can find the suspicious sid.

I run into a discussion on a forum, and found a solution as follows:

Shutdown OEM, login as SYSMAN user and restart the provisioning daemon by executing the two packaged procedures

SYSMAN> execute MGMT_PAF_UTL.STOP_DAEMON
PL/SQL procedure successfully completed.

SYSMAN> execute MGMT_PAF_UTL.START_DAEMON
PL/SQL procedure successfully completed.

Start OEM again and the problem is gone.

And it worked.
It seems like a bug inside oracle.