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diff --git a/ACE/ace/Timer_Queue_Adapters.h b/ACE/ace/Timer_Queue_Adapters.h
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+// -*- C++ -*-
+
+//=============================================================================
+/**
+ *  @file    Timer_Queue_Adapters.h
+ *
+ *  $Id$
+ *
+ *  @author Douglas C. Schmidt <schmidt@cs.wustl.edu> and
+ *          Carlos O'Ryan <coryan@uci.edu>
+ */
+//=============================================================================
+
+#ifndef ACE_TIMER_QUEUE_ADAPTERS_H
+#define ACE_TIMER_QUEUE_ADAPTERS_H
+#include /**/ "ace/pre.h"
+
+#include "ace/Task.h"
+
+#if !defined (ACE_LACKS_PRAGMA_ONCE)
+# pragma once
+#endif /* ACE_LACKS_PRAGMA_ONCE */
+
+#include "ace/Signal.h"
+#include "ace/Sig_Handler.h"
+#include "ace/Condition_Recursive_Thread_Mutex.h"
+
+#if defined (ACE_HAS_DEFERRED_TIMER_COMMANDS)
+#  include "ace/Unbounded_Queue.h"
+ACE_BEGIN_VERSIONED_NAMESPACE_DECL
+class ACE_Command_Base;
+ACE_END_VERSIONED_NAMESPACE_DECL
+#endif /* ACE_HAS_DEFERRED_TIMER_COMMANDS */
+
+ACE_BEGIN_VERSIONED_NAMESPACE_DECL
+
+class ACE_Sig_Set;
+
+/**
+ * @class ACE_Async_Timer_Queue_Adapter
+ *
+ * @brief Adapts an ACE timer queue to be driven asynchronously using signals.
+ *
+ * This implementation uses the ACE_OS::ualarm call, to generate
+ * the SIGARLM signal that is caught by this class.
+ *
+ * @note This adapter only works on platforms that support ualarm().
+ * POSIX platforms generally do; Windows and some others do not.
+ *
+ * @todo This adapter does not automatically reschedule repeating timers.
+ */
+template <class TQ>
+class ACE_Async_Timer_Queue_Adapter : public ACE_Event_Handler
+{
+public:
+  typedef TQ TIMER_QUEUE;
+
+  /// Constructor
+  /**
+   * Register the SIGALRM handler.  If @a mask == 0 then block all
+   * signals when @c SIGALRM is run.  Otherwise, just block the signals
+   * indicated in @a mask.
+   */
+  ACE_Async_Timer_Queue_Adapter (ACE_Sig_Set *mask = 0);
+
+  /// Schedule the timer according to the semantics of the
+  /// ACE_Timer_List.
+  /**
+   * This timer gets dispatched via a signal, rather than by a user
+   * calling expire().  Note that interval timers are not implemented
+   * yet.
+   */
+  long schedule (ACE_Event_Handler *type,
+                 const void *act,
+                 const ACE_Time_Value &future_time,
+                 const ACE_Time_Value &interval = ACE_Time_Value::zero);
+
+  /// Cancel the @a timer_id and pass back the @a act if an address is
+  /// passed in.
+  int cancel (long timer_id, const void **act = 0);
+
+  /// Dispatch all timers with expiry time at or before the current time.
+  /// Returns the number of timers expired.
+  int expire (void);
+
+  /// Return a reference to the underlying timer queue.
+  TQ &timer_queue (void);
+
+private:
+  /// Perform the logic to compute the new ualarm(2) setting.
+  virtual int schedule_ualarm (void);
+
+  /// Called back by @c SIGALRM handler.
+  virtual int handle_signal (int signum, siginfo_t *, ucontext_t *);
+
+  /// Handler for the @c SIGALRM signal, so that we can access our state
+  /// without requiring any global variables.
+  ACE_Sig_Handler sig_handler_;
+
+  /// Implementation of the timer queue (e.g., ACE_Timer_List,
+  /// ACE_Timer_Heap, etc.).
+  TQ timer_queue_;
+
+  /// Mask of signals to be blocked when we're servicing @c SIGALRM.
+  ACE_Sig_Set mask_;
+};
+
+/**
+ * @class ACE_Thread_Timer_Queue_Adapter
+ *
+ * @brief Adapts an ACE timer queue using a separate thread for dispatching.
+ *
+ * This implementation uses a separate thread to dispatch the timers.
+ * The base queue need not be thread safe; this class takes all the
+ * necessary locks.
+ *
+ * @note This is a case where template parameters will be useful, but
+ * (IMHO) the effort and portability problems discourage their
+ * use.
+ *
+ */
+template <class TQ>
+class ACE_Thread_Timer_Queue_Adapter : public ACE_Task_Base
+{
+public:
+  /// Trait for the underlying queue type.
+  typedef TQ TIMER_QUEUE;
+
+# if defined (ACE_HAS_DEFERRED_TIMER_COMMANDS)
+
+  /// Typedef for the position at which to enqueue a deferred
+  /// execution command.
+  enum COMMAND_ENQUEUE_POSITION {HEAD, TAIL};
+
+# endif /* ACE_HAS_DEFERRED_TIMER_COMMANDS */
+
+  /// Creates the timer queue.  Activation of the task is the user's
+  /// responsibility. Optionally a pointer to a timer queue can be passed,
+  /// when no pointer is passed, a TQ is dynamically created
+  ACE_Thread_Timer_Queue_Adapter (ACE_Thread_Manager * = ACE_Thread_Manager::instance (),
+                                  TQ* timer_queue = 0);
+
+  /// Destructor.
+  virtual ~ACE_Thread_Timer_Queue_Adapter (void);
+
+  /// Schedule the timer according to the semantics of the <TQ>; wakes
+  /// up the dispatching thread.
+  long schedule (ACE_Event_Handler *handler,
+                 const void *act,
+                 const ACE_Time_Value &future_time,
+                 const ACE_Time_Value &interval = ACE_Time_Value::zero);
+
+  /// Cancel the @a timer_id and return the @a act parameter if an
+  /// address is passed in. Also wakes up the dispatching thread.
+  int cancel (long timer_id, const void **act = 0);
+
+  /// Runs the dispatching thread.
+  virtual int svc (void);
+
+  /// Inform the dispatching thread that it should terminate.
+  virtual void deactivate (void);
+
+  /// Access the locking mechanism, useful for iteration.
+  ACE_SYNCH_RECURSIVE_MUTEX &mutex (void);
+
+  /// Set a user-specified timer queue.
+  int timer_queue (TQ *tq);
+
+  /// Return the current <TQ>.
+  TQ *timer_queue (void) const;
+
+  /// Return the thread id of our active object.
+  ACE_thread_t thr_id (void) const;
+
+  /**
+   * We override the default activate() method so that we can ensure
+   * that only a single thread is ever spawned.  Otherwise, too many
+   * weird things can happen...
+   */
+  virtual int activate (long flags = THR_NEW_LWP | THR_JOINABLE,
+                        int n_threads = 1,
+                        int force_active = 0,
+                        long priority = ACE_DEFAULT_THREAD_PRIORITY,
+                        int grp_id = -1,
+                        ACE_Task_Base *task = 0,
+                        ACE_hthread_t thread_handles[] = 0,
+                        void *stack[] = 0,
+                        size_t stack_size[] = 0,
+                        ACE_thread_t thread_names[] = 0);
+
+# if defined (ACE_HAS_DEFERRED_TIMER_COMMANDS)
+
+  /**
+   * Enqueues a command object for execution just before waiting on the next
+   * timer event. This allows deferred execution of commands that cannot
+   * be performed in the timer event handler context, such as registering
+   * or cancelling timers on platforms where the timer queue mutex is not
+   * recursive.
+   */
+  int enqueue_command (ACE_Command_Base *command_,
+                       COMMAND_ENQUEUE_POSITION pos = TAIL);
+
+# endif /* ACE_HAS_DEFERRED_TIMER_COMMANDS */
+
+private:
+
+# if defined (ACE_HAS_DEFERRED_TIMER_COMMANDS)
+  /// Dispatches all command objects enqueued in the most
+  /// recent event handler context.
+  int dispatch_commands (void);
+
+  /// Queue of commands for deferred execution.
+  ACE_Unbounded_Queue<ACE_Command_Base *> command_queue_;
+
+  /// The mutual exclusion mechanism for the command queue.
+  ACE_SYNCH_MUTEX command_mutex_;
+# endif /* ACE_HAS_DEFERRED_TIMER_COMMANDS */
+
+  /// The underlying Timer_Queue.
+  TQ* timer_queue_;
+
+  /// Keeps track of whether we should delete the timer queue (if we
+  /// didn't create it, then we don't delete it).
+  int delete_timer_queue_;
+
+  /// The mutual exclusion mechanism that is required to use the
+  /// <condition_>.
+  ACE_SYNCH_RECURSIVE_MUTEX mutex_;
+
+  /**
+   * The dispatching thread sleeps on this condition while waiting to
+   * dispatch the next timer; it is used to wake it up if there is a
+   * change on the timer queue.
+   */
+  ACE_SYNCH_RECURSIVE_CONDITION condition_;
+
+  /// When deactivate is called this variable turns to false and the
+  /// dispatching thread is signalled, to terminate its main loop.
+  int active_;
+
+  /// Thread id of our active object task.
+  ACE_thread_t thr_id_;
+};
+
+ACE_END_VERSIONED_NAMESPACE_DECL
+
+#if defined (__ACE_INLINE__)
+# include "ace/Timer_Queue_Adapters.inl"
+#endif /* __ACE_INLINE__ */
+
+#if defined (ACE_TEMPLATES_REQUIRE_SOURCE)
+# include "ace/Timer_Queue_Adapters.cpp"
+#endif /* ACE_TEMPLATES_REQUIRE_SOURCE */
+
+#if defined (ACE_TEMPLATES_REQUIRE_PRAGMA)
+# pragma implementation ("Timer_Queue_Adapters.cpp")
+#endif /* ACE_TEMPLATES_REQUIRE_PRAGMA */
+
+#include /**/ "ace/post.h"
+#endif /* ACE_TIMER_QUEUE_ADAPTERS_H */