This exception has been found when try to run RelayDemo comes with the jgroups-3.0.0.CR5.jar. The exact same run has been successful with jgroups-2.12.1.Final.jar.

Here is the details of the exception.

Oct 21, 2011 12:37:43 AM org.jgroups.logging.JDKLogImpl error
SEVERE: failed installing view
java.lang.IllegalAccessException: Class org.jgroups.util.Util can not access a member of class org.jgroups.protocols.REL
AY$ViewData with modifiers "protected"
at sun.reflect.Reflection.ensureMemberAccess(Reflection.java:65)
at java.lang.Class.newInstance0(Class.java:349)
at java.lang.Class.newInstance(Class.java:308)
at org.jgroups.util.Util.streamableFromByteBuffer(Util.java:668)
at org.jgroups.protocols.RELAY.installView(RELAY.java:272)
at org.jgroups.protocols.RELAY.up(RELAY.java:200)
at org.jgroups.protocols.pbcast.STATE_TRANSFER.up(STATE_TRANSFER.java:178)
at org.jgroups.protocols.FRAG2.up(FRAG2.java:181)
at org.jgroups.protocols.FlowControl.up(FlowControl.java:400)
at org.jgroups.protocols.FlowControl.up(FlowControl.java:418)
at org.jgroups.protocols.pbcast.GMS.up(GMS.java:865)
at org.jgroups.protocols.pbcast.STABLE.up(STABLE.java:244)
at org.jgroups.protocols.UNICAST.up(UNICAST.java:297)
at org.jgroups.protocols.pbcast.NAKACK.handleMessage(NAKACK.java:719)
at org.jgroups.protocols.pbcast.NAKACK.up(NAKACK.java:547)
at org.jgroups.protocols.BARRIER.up(BARRIER.java:126)
at org.jgroups.protocols.VERIFY_SUSPECT.up(VERIFY_SUSPECT.java:134)
at org.jgroups.protocols.FD_ALL.up(FD_ALL.java:171)
at org.jgroups.protocols.FD_SOCK.up(FD_SOCK.java:273)
at org.jgroups.protocols.MERGE2.up(MERGE2.java:208)
at org.jgroups.protocols.Discovery.up(Discovery.java:335)
at org.jgroups.protocols.TP.passMessageUp(TP.java:1091)
at org.jgroups.protocols.TP$3.run(TP.java:1014)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:662)
Oct 21, 2011 12:37:43 AM org.jgroups.logging.JDKLogImpl info
INFO: JGroups version: 3.0.0.CR5