*/
@Override
protected synchronized void internalLock(String sessionId, String nodeIdentifier) throws LockException
{
CacheableSessionLockManager session = sessionLockManagers.get(sessionId);
if (session != null && session.containsPendingLock(nodeIdentifier))
{
LockData lockData = session.getPendingLock(nodeIdentifier);
// this will return null if success. And old data if something exists...
LockData oldLockData = (LockData)PrivilegedISPNCacheHelper.putIfAbsent(cache, nodeIdentifier, lockData);