OPENJPA-2055: Added code to account for IPv6 addresses.

git-svn-id: https://svn.apache.org/repos/asf/openjpa/trunk@1295698 13f79535-47bb-0310-9956-ffa450edef68

openjpa-lib/src/main/java/org/apache/openjpa/lib/util/UUIDGenerator.java

@@ -118,7 +118,13 @@ public class UUIDGenerator {
 
         IP = new byte[6];
         RANDOM.nextBytes(IP);
-        System.arraycopy(ip, 0, IP, 2, ip.length);        
+
+        //OPENJPA-2055: account for the fact that 'getAddress'
+        //may return an IPv6 address which is 16 bytes wide.
+        for( int i = 0 ; i < ip.length; ++i ) {
+            IP[2+(i%4)] ^= ip[i];
+        }
+        
         type1Initialized = true;
     }