this.dialogTable = new Hashtable();
this.dialogTable = new ConcurrentHashMap();
	protected SIPTransactionStack() {		super();		this.transactionTableSize = -1;		// a set of methods that result in dialog creation.		this.dialogCreatingMethods = new HashSet();		// Standard set of methods that create dialogs.		this.dialogCreatingMethods.add(Request.REFER);		this.dialogCreatingMethods.add(Request.INVITE);		this.dialogCreatingMethods.add(Request.SUBSCRIBE);		// Notify may or may not create a dialog. This is handled in		// the code.		// Create the transaction collections		clientTransactions = Collections.synchronizedList(new ArrayList());		serverTransactions = Collections.synchronizedList(new ArrayList());		// Dialog dable.		this.dialogTable = new Hashtable();		clientTransactionTable = new Hashtable();		serverTransactionTable = new Hashtable();		// Start the timer event thread.		this.timer = new Timer();		this.pendingRecordScanner = new Thread(new PendingRecordScanner(this));		this.pendingRecordScanner.setDaemon(true);		this.pendingTransactions = new HashSet();		pendingRecords = Collections.synchronizedList(new ArrayList());		pendingRecordScanner.setName("PendingRecordScanner");		pendingRecordScanner.start();		//endif		//	}