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diff --git a/libs/glibmm2/glibmm/dispatcher.h b/libs/glibmm2/glibmm/dispatcher.h
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+++ b/libs/glibmm2/glibmm/dispatcher.h
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+// -*- c++ -*-
+#ifndef _GLIBMM_DISPATCHER_H
+#define _GLIBMM_DISPATCHER_H
+
+/* $Id$ */
+
+/* Copyright 2002 The gtkmm Development Team
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the Free
+ * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <sigc++/sigc++.h>
+#include <glibmm/main.h>
+
+
+namespace Glib
+{
+
+#ifndef DOXYGEN_SHOULD_SKIP_THIS
+class DispatchNotifier;
+#endif
+
+/** Signal class for inter-thread communication.
+ * @ingroup Threads
+ * Glib::Dispatcher works similar to sigc::signal<void>.  But unlike normal
+ * signals, the notification happens asynchronously through a pipe.  This is
+ * a simple and efficient way of communicating between threads, and especially
+ * useful in a thread model with a single GUI thread.
+ *
+ * No mutex locking is involved, apart from the operating system's internal
+ * I/O locking.  That implies some usage rules:
+ *
+ * @li Only one thread may connect to the signal and receive notification, but
+ * multiple senders are allowed even without locking.
+ * @li The GLib main loop must run in the receiving thread (this will be the
+ * GUI thread usually).
+ * @li The Dispatcher object must be instantiated by the receiver thread.
+ * @li The Dispatcher object should be instantiated before creating any of the
+ * sender threads, if you want to avoid extra locking.
+ *
+ * Notes about performance:
+ *
+ * @li After instantiation, Glib::Dispatcher will never lock any mutexes on its
+ * own.  The interaction with the GLib main loop might involve locking on the
+ * @em receiver side.  The @em sender side, however, is guaranteed not to lock,
+ * except for internal locking in the <tt>%write()</tt> system call.
+ * @li All Dispatcher instances of a receiver thread share the same pipe.  That
+ * is, if you use Glib::Dispatcher only to notify the GUI thread, only one pipe
+ * is created no matter how many Dispatcher objects you have.
+ */
+class Dispatcher
+{
+public:
+  /** Create new Dispatcher instance using the default main context.
+   * @throw Glib::FileError
+   */
+  Dispatcher();
+  /** Create new Dispatcher instance using an arbitrary main context.
+   * @throw Glib::FileError
+   */
+  explicit Dispatcher(const Glib::RefPtr<MainContext>& context);
+  ~Dispatcher();
+
+  void emit();
+  void operator()();
+
+  sigc::connection connect(const sigc::slot<void>& slot);
+
+private:
+  sigc::signal<void> signal_;
+  DispatchNotifier*   notifier_;
+
+  // noncopyable
+  Dispatcher(const Dispatcher&);
+  Dispatcher& operator=(const Dispatcher&);
+
+#ifndef DOXYGEN_SHOULD_SKIP_THIS
+  friend class Glib::DispatchNotifier;
+#endif
+};
+
+/*! A Glib::Dispatcher example.
+ * @example thread/dispatcher.cc
+ */
+
+} // namespace Glib
+
+
+#endif /* _GLIBMM_DISPATCHER_H */
+