OEM 2.1 Notification problems

[Ghenadie]

Greetings!
I have a problem. OEM won't send notification of events and jobs by email although the test works. I've looked at all the messages on the metalink with similar problems and got no solution.

Here is the error from oms.nohup file:
java.lang.NullPointerException
at java.lang.String.<init>(String.java)
at oracle.sysman.vdm.VdmNotificationManager.getNotification(VdmNotificationManager.java:2376)
at oracle.sysman.vdm.VdmNotificationManager.preProcessUiOperation(VdmNotificationManager.java:1089)
at oracle.sysman.vdm.VdmNotificationManager.processOperation(VdmNotificationManager.java:899)
at oracle.sysman.vdiBaseComps.VdiExecuter.run(VdiExecuter.java:24)
at oracle.sysman.vtaGallery.threadPoolManager.WorkerThread.run(Worker.java:277)
[vdm:Thread-18][2001-2-16:7:47:6:950] Vdm - tid[29] ERROR Notification #528 not found

Warning in the dbsnmpw.log
NMS-00001: Warning: dbsnmp unable to connect to SNMP master agent

Need a piece of advise...