NPE if additional_data is not set

If the cluster setup doesn't support the jgroups additional_data feature, the 2nd and later nodes in the cluster will crash with an NPE.

From the forum post:

This is the method from the org.jboss.ha.framework.server.HAPartitionImpl which is crashing :
Code:

protected void verifyNodeIsUnique (Vector javaGroupIpAddresses) throws Exception
{
byte[] localUniqueName = this.localJGAddress.getAdditionalData();
if (localUniqueName == null)
log.warn("No additional information has been found in the JavaGroup address: " +
"make sure you are running with a correct version of JGroups and that the protocol " +
" you are using supports the 'additionalData' behaviour");

for (int i = 0; i < javaGroupIpAddresses.size(); i++)
{
IpAddress address = (IpAddress) javaGroupIpAddresses.elementAt;
if (!address.equals(this.localJGAddress))

{ if (localUniqueName.equals(address.getAdditionalData())) throw new Exception ("Local node removed from cluster (" + this.localJGAddress + "): another node (" + address + ") publicizing the same name was already there"); }

}
}

The "if (localUniqueName.equals(address.getAdditionalData()))" is the one causing the NPE.

Method should return after the WARN.

I believe the TUNNEL protocol does not properly support additional_data, but haven't 100% confirmed this. That's a separate issue, but is the likely usage that will expose this issue.