I recently password protected my listener. But now, when I look at the listener.log file, I see a lot of these:

19-MAY-2006 08:27:00 * (CONNECT_DATA=(SID=PROD)(SERVER=DEDICATED)(CID=(PROGRAM=dbsnmp)(HOST=OEMserver)(USER=oracle))) * status * 1169
TNS-01169: The listener has not recognized the password

There's a lot of these coming in every minute.

I believe this is the polling that OEM does for the "Oracle Net Up Down" event to check on the status of the listener.

So how does OEM monitor listeners if the listener has a password?