[SNMP4J] Notification issues

[Matthias Wiesmann]

Hello everybody, Frank,

I think I have found two other issues in the notification mechanism.

First the data structures seems unable to handle concurrent
modification of the notification data structures whiles a notification
is sent.

I got the following exception, when trying to remove a notification
entry while notifications are sent at a high rate.

java.util.ConcurrentModificationException
	at java.util.TreeMap$PrivateEntryIterator.nextEntry(TreeMap.java:1031)
	at java.util.TreeMap$ValueIterator.next(TreeMap.java:1064)
	at org.snmp4j.agent.mo.snmp.NotificationOriginatorImpl.notify(NotificationOriginatorImpl.java:108)
	at jp.ac.jaist.snmpd.FDAgent$AgentHub.notify(FDAgent.java:64)

Second, it seems that if you create a notification entry, disable it
(by changing its status) and enable it again, it does not work.

Cheers.

Matthias