--- a/dom/plugins/Makefile.in
+++ b/dom/plugins/Makefile.in
@@ -90,17 +90,29 @@ EXPORTS_mozilla/plugins = \
 
 MODULE           = dom
 LIBRARY_NAME     = domplugins_s
 LIBXUL_LIBRARY   = 1
 FORCE_STATIC_LIB = 1
 EXPORT_LIBRARY = 1
 ENABLE_CXX_EXCEPTIONS = 1
 
+ifeq ($(MOZ_ENABLE_QT),1)
+MOCSRCS = \
+  moc_NestedLoopTimer.cpp \
+  $(NULL)
+
+QTSRCS = \
+  NestedLoopTimer.cpp \
+  $(NULL)
+endif
+
 CPPSRCS = \
+  $(MOCSRCS) \
+  $(QTSRCS) \
   ChildAsyncCall.cpp \
   ChildTimer.cpp \
   PluginMessageUtils.cpp \
   PluginInstanceChild.cpp \
   PluginInstanceParent.cpp \
   PluginModuleChild.cpp \
   PluginModuleParent.cpp \
   PluginProcessChild.cpp \

new file mode 100644
--- /dev/null
+++ b/dom/plugins/NestedLoopTimer.cpp
@@ -0,0 +1,80 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * vim: sw=4 ts=4 et :
+ * ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is Mozilla Plugin App.
+ *
+ * The Initial Developer of the Original Code is mozilla.org code.
+ * Portions created by the Initial Developer are Copyright (C) 2010
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributors(s):
+ *  Tero Koskinen <tero.koskinen@iki.fi>  (Original Author)
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#include <QtCore/QTimer>
+
+#include "NestedLoopTimer.h"
+#include "mozilla/plugins/PluginModuleChild.h"
+
+namespace mozilla {
+namespace plugins {
+
+NestedLoopTimer::NestedLoopTimer(PluginModuleChild *pmc):
+     QObject(), mModule(pmc), mQTimer(NULL)
+{
+}
+
+NestedLoopTimer::~NestedLoopTimer()
+{
+    if (mQTimer) {
+        mQTimer->stop();
+        delete mQTimer;
+        mQTimer = NULL;
+    }
+}
+
+void NestedLoopTimer::timeOut()
+{
+    // just detected a nested loop; start a timer that will
+    // periodically rpc-call back into the browser and process some
+    // events
+    mQTimer = new QTimer(this);
+    QObject::connect(mQTimer, SIGNAL(timeout()), this,
+                     SLOT(processSomeEvents()));
+    mQTimer->setInterval(kNestedLoopDetectorIntervalMs);
+    mQTimer->start();
+}
+
+void NestedLoopTimer::processSomeEvents()
+{
+    if (mModule)
+        mModule->CallProcessSomeEvents();
+}
+
+} /* namespace plugins */
+} /* namespace mozilla */

new file mode 100644
--- /dev/null
+++ b/dom/plugins/NestedLoopTimer.h
@@ -0,0 +1,71 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * vim: sw=4 ts=4 et :
+ * ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is Mozilla Plugin App.
+ *
+ * The Initial Developer of the Original Code is mozilla.org code.
+ * Portions created by the Initial Developer are Copyright (C) 2010
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributors(s):
+ *  Tero Koskinen <tero.koskinen@iki.fi>  (Original Author)
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#ifndef NESTEDLOOPTIMER_H
+#define NESTEDLOOPTIMER_H
+
+#include <QtCore/QObject>
+
+class QTimer;
+
+namespace mozilla {
+namespace plugins {
+
+class PluginModuleChild;
+
+class NestedLoopTimer: public QObject
+{
+    Q_OBJECT
+public:
+    NestedLoopTimer(PluginModuleChild *pmc);
+
+    virtual ~NestedLoopTimer();
+
+public Q_SLOTS:
+    virtual void timeOut();
+    virtual void processSomeEvents();
+   
+private:
+    PluginModuleChild *mModule;
+    QTimer *mQTimer;
+};
+
+} /* namespace plugins */
+} /* namespace mozilla */
+
+#endif

--- a/dom/plugins/PluginModuleChild.cpp
+++ b/dom/plugins/PluginModuleChild.cpp
@@ -33,17 +33,19 @@
  * decision by deleting the provisions above and replace them with the notice
  * and other provisions required by the GPL or the LGPL. If you do not delete
  * the provisions above, a recipient may use your version of this file under
  * the terms of any one of the MPL, the GPL or the LGPL.
  *
  * ***** END LICENSE BLOCK ***** */
 
 #ifdef MOZ_WIDGET_QT
+#include <QtCore/QTimer>
 #include "nsQAppInstance.h"
+#include "NestedLoopTimer.h"
 #endif
 
 #include "mozilla/plugins/PluginModuleChild.h"
 
 #ifdef MOZ_WIDGET_GTK2
 #include <gtk/gtk.h>
 #endif
 
@@ -91,16 +93,18 @@ static bool gDelayFlashFocusReplyUntilEv
 PluginModuleChild::PluginModuleChild() :
     mLibrary(0),
     mShutdownFunc(0),
     mInitializeFunc(0)
 #if defined(OS_WIN) || defined(OS_MACOSX)
   , mGetEntryPointsFunc(0)
 #elif defined(MOZ_WIDGET_GTK2)
   , mNestedLoopTimerId(0)
+#elif defined(MOZ_WIDGET_QT)
+  , mNestedLoopTimerObject(0)
 #endif
 #ifdef OS_WIN
   , mNestedEventHook(NULL)
   , mGlobalCallWndProcHook(NULL)
 #endif
 {
     NS_ASSERTION(!gInstance, "Something terribly wrong here!");
     memset(&mFunctions, 0, sizeof(mFunctions));
@@ -441,16 +445,36 @@ void
 PluginModuleChild::ExitedCxxStack()
 {
     NS_ABORT_IF_FALSE(0 < mNestedLoopTimerId,
                       "nested loop timeout not scheduled");
 
     g_source_remove(mNestedLoopTimerId);
     mNestedLoopTimerId = 0;
 }
+#elif defined (MOZ_WIDGET_QT)
+
+void
+PluginModuleChild::EnteredCxxStack()
+{
+    NS_ABORT_IF_FALSE(mNestedLoopTimerObject == NULL,
+                      "previous timer not descheduled");
+    mNestedLoopTimerObject = new NestedLoopTimer(this);
+    QTimer::singleShot(kNestedLoopDetectorIntervalMs,
+                       mNestedLoopTimerObject, SLOT(timeOut()));
+}
+
+void
+PluginModuleChild::ExitedCxxStack()
+{
+    NS_ABORT_IF_FALSE(mNestedLoopTimerObject != NULL,
+                      "nested loop timeout not scheduled");
+    delete mNestedLoopTimerObject;
+    mNestedLoopTimerObject = NULL;
+}
 
 #endif
 
 bool
 PluginModuleChild::InitGraphics()
 {
 #if defined(MOZ_WIDGET_GTK2)
     // Work around plugins that don't interact well with GDK

--- a/dom/plugins/PluginModuleChild.h
+++ b/dom/plugins/PluginModuleChild.h
@@ -84,16 +84,21 @@
 typedef NS_NPAPIPLUGIN_CALLBACK(NPError, NP_GETENTRYPOINTS) (NPPluginFuncs* pCallbacks);
 typedef NS_NPAPIPLUGIN_CALLBACK(NPError, NP_PLUGININIT) (const NPNetscapeFuncs* pCallbacks);
 typedef NS_NPAPIPLUGIN_CALLBACK(NPError, NP_PLUGINUNIXINIT) (const NPNetscapeFuncs* pCallbacks, NPPluginFuncs* fCallbacks);
 typedef NS_NPAPIPLUGIN_CALLBACK(NPError, NP_PLUGINSHUTDOWN) (void);
 
 namespace mozilla {
 namespace plugins {
 
+#ifdef MOZ_WIDGET_QT
+class NestedLoopTimer;
+static const int kNestedLoopDetectorIntervalMs = 90;
+#endif
+
 class PluginScriptableObjectChild;
 class PluginInstanceChild;
 
 class PluginModuleChild : public PPluginModuleChild
 {
 protected:
     NS_OVERRIDE
     virtual mozilla::ipc::RPCChannel::RacyRPCPolicy
@@ -193,16 +198,22 @@ private:
 #if defined(MOZ_WIDGET_GTK2)
     static gboolean DetectNestedEventLoop(gpointer data);
     static gboolean ProcessBrowserEvents(gpointer data);
 
     NS_OVERRIDE
     virtual void EnteredCxxStack();
     NS_OVERRIDE
     virtual void ExitedCxxStack();
+#elif defined(MOZ_WIDGET_QT)
+
+    NS_OVERRIDE
+    virtual void EnteredCxxStack();
+    NS_OVERRIDE
+    virtual void ExitedCxxStack();
 #endif
 
     std::string mPluginFilename;
     PRLibrary* mLibrary;
     nsCString mUserAgent;
 
     // we get this from the plugin
     NP_PLUGINSHUTDOWN mShutdownFunc;
@@ -249,16 +260,18 @@ private:
     guint mNestedLoopTimerId;
 #  ifdef DEBUG
     // Depth of the stack of calls to g_main_context_dispatch before any
     // nested loops are run.  This is 1 when IPC calls are dispatched from
     // g_main_context_iteration, or 0 when dispatched directly from
     // MessagePumpForUI.
     int mTopLoopDepth;
 #  endif
+#elif defined (MOZ_WIDGET_QT)
+    NestedLoopTimer *mNestedLoopTimerObject;
 #endif
 
     struct NPObjectData : public nsPtrHashKey<NPObject>
     {
         NPObjectData(const NPObject* key)
             : nsPtrHashKey<NPObject>(key)
             , instance(NULL)
             , actor(NULL)

--- a/dom/plugins/PluginModuleParent.cpp
+++ b/dom/plugins/PluginModuleParent.cpp
@@ -34,16 +34,20 @@
  * the provisions above, a recipient may use your version of this file under
  * the terms of any one of the MPL, the GPL or the LGPL.
  *
  * ***** END LICENSE BLOCK ***** */
 
 #ifdef MOZ_WIDGET_GTK2
 #include <glib.h>
 #endif
+#ifdef MOZ_WIDGET_QT
+#include <QtCore/QCoreApplication>
+#include <QtCore/QEventLoop>
+#endif
 
 #include "base/process_util.h"
 
 #include "mozilla/unused.h"
 #include "mozilla/ipc/SyncChannel.h"
 #include "mozilla/plugins/PluginModuleParent.h"
 #include "mozilla/plugins/BrowserStreamParent.h"
 #include "PluginIdentifierParent.h"
@@ -749,17 +753,30 @@ PluginModuleParent::AnswerNPN_GetValue_W
                                                       bool* aBoolVal)
 {
     NPBool boolVal = false;
     *aError = mozilla::plugins::parent::_getvalue(nsnull, aVariable, &boolVal);
     *aBoolVal = boolVal ? true : false;
     return true;
 }
 
-#if !defined(MOZ_WIDGET_GTK2)
+#if defined(MOZ_WIDGET_QT)
+static const int kMaxtimeToProcessEvents = 30;
+bool
+PluginModuleParent::AnswerProcessSomeEvents()
+{
+    PLUGIN_LOG_DEBUG(("Spinning mini nested loop ..."));
+    QCoreApplication::processEvents(QEventLoop::AllEvents, kMaxtimeToProcessEvents);
+
+    PLUGIN_LOG_DEBUG(("... quitting mini nested loop"));
+
+    return true;
+}
+
+#elif !defined(MOZ_WIDGET_GTK2)
 bool
 PluginModuleParent::AnswerProcessSomeEvents()
 {
     NS_RUNTIMEABORT("unreached");
     return false;
 }
 
 #else