Index: /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UIMachineLogic.cpp
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UIMachineLogic.cpp	(revision 54159)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UIMachineLogic.cpp	(revision 54160)
@@ -847,5 +847,5 @@
 
     /* Guest additions state-change updater: */
-    connect(uisession(), SIGNAL(sigAdditionsStateChange()), this, SLOT(sltAdditionsStateChanged()));
+    connect(uisession(), SIGNAL(sigAdditionsStateActualChange()), this, SLOT(sltAdditionsStateChanged()));
 
     /* Mouse capability state-change updater: */
Index: /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UISession.cpp
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UISession.cpp	(revision 54159)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UISession.cpp	(revision 54160)
@@ -907,7 +907,10 @@
         m_fIsGuestSupportsSeamless = fIsGuestSupportsSeamless;
 
-        /* Notify listeners about guest additions state changed: */
-        emit sigAdditionsStateChange();
-    }
+        /* Notify listeners about guest additions state really changed: */
+        emit sigAdditionsStateActualChange();
+    }
+
+    /* Notify listeners about guest additions state event came: */
+    emit sigAdditionsStateChange();
 }
 
Index: /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UISession.h
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UISession.h	(revision 54159)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UISession.h	(revision 54160)
@@ -267,4 +267,5 @@
     void sigMachineStateChange();
     void sigAdditionsStateChange();
+    void sigAdditionsStateActualChange();
     void sigNetworkAdapterChange(const CNetworkAdapter &networkAdapter);
     void sigMediumChange(const CMediumAttachment &mediumAttachment);
Index: /trunk/src/VBox/Frontends/VirtualBox/src/runtime/fullscreen/UIMachineLogicFullscreen.cpp
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/runtime/fullscreen/UIMachineLogicFullscreen.cpp	(revision 54159)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/runtime/fullscreen/UIMachineLogicFullscreen.cpp	(revision 54160)
@@ -335,4 +335,7 @@
 void UIMachineLogicFullscreen::sltCheckForRequestedVisualStateType()
 {
+    LogRel(("UIMachineLogicFullscreen::sltCheckForRequestedVisualStateType: Requested-state=%d, Machine-state=%d\n",
+            uisession()->requestedVisualState(), uisession()->machineState()));
+
     /* Do not try to change visual-state type if machine was not started yet: */
     if (!uisession()->isRunning() && !uisession()->isPaused())
Index: /trunk/src/VBox/Frontends/VirtualBox/src/runtime/fullscreen/UIMachineViewFullscreen.cpp
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/runtime/fullscreen/UIMachineViewFullscreen.cpp	(revision 54159)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/runtime/fullscreen/UIMachineViewFullscreen.cpp	(revision 54160)
@@ -129,5 +129,5 @@
 
     /* Guest additions state-change updater: */
-    connect(uisession(), SIGNAL(sigAdditionsStateChange()), this, SLOT(sltAdditionsStateChanged()));
+    connect(uisession(), SIGNAL(sigAdditionsStateActualChange()), this, SLOT(sltAdditionsStateChanged()));
 }
 
Index: /trunk/src/VBox/Frontends/VirtualBox/src/runtime/normal/UIMachineLogicNormal.cpp
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/runtime/normal/UIMachineLogicNormal.cpp	(revision 54159)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/runtime/normal/UIMachineLogicNormal.cpp	(revision 54160)
@@ -65,4 +65,7 @@
 void UIMachineLogicNormal::sltCheckForRequestedVisualStateType()
 {
+    LogRel(("UIMachineLogicNormal::sltCheckForRequestedVisualStateType: Requested-state=%d, Machine-state=%d\n",
+            uisession()->requestedVisualState(), uisession()->machineState()));
+
     /* Do not try to change visual-state type if machine was not started yet: */
     if (!uisession()->isRunning() && !uisession()->isPaused())
@@ -83,4 +86,7 @@
                 uisession()->changeVisualState(UIVisualStateType_Seamless);
             }
+            else
+                LogRel(("UIMachineLogicNormal::sltCheckForRequestedVisualStateType: "
+                        "Rejecting 'seamless' as is it not yet supported...\n"));
             break;
         }
Index: /trunk/src/VBox/Frontends/VirtualBox/src/runtime/normal/UIMachineViewNormal.cpp
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/runtime/normal/UIMachineViewNormal.cpp	(revision 54159)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/runtime/normal/UIMachineViewNormal.cpp	(revision 54160)
@@ -124,5 +124,5 @@
 
     /* Guest additions state-change updater: */
-    connect(uisession(), SIGNAL(sigAdditionsStateChange()), this, SLOT(sltAdditionsStateChanged()));
+    connect(uisession(), SIGNAL(sigAdditionsStateActualChange()), this, SLOT(sltAdditionsStateChanged()));
 }
 
Index: /trunk/src/VBox/Frontends/VirtualBox/src/runtime/seamless/UIMachineLogicSeamless.cpp
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/runtime/seamless/UIMachineLogicSeamless.cpp	(revision 54159)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/runtime/seamless/UIMachineLogicSeamless.cpp	(revision 54160)
@@ -125,4 +125,7 @@
 void UIMachineLogicSeamless::sltCheckForRequestedVisualStateType()
 {
+    LogRel(("UIMachineLogicSeamless::sltCheckForRequestedVisualStateType: Requested-state=%d, Machine-state=%d\n",
+            uisession()->requestedVisualState(), uisession()->machineState()));
+
     /* Do not try to change visual-state type if machine was not started yet: */
     if (!uisession()->isRunning() && !uisession()->isPaused())
Index: /trunk/src/VBox/Frontends/VirtualBox/src/runtime/seamless/UIMachineViewSeamless.cpp
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/runtime/seamless/UIMachineViewSeamless.cpp	(revision 54159)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/runtime/seamless/UIMachineViewSeamless.cpp	(revision 54160)
@@ -144,5 +144,5 @@
 
     /* Guest additions state-change updater: */
-    connect(uisession(), SIGNAL(sigAdditionsStateChange()), this, SLOT(sltAdditionsStateChanged()));
+    connect(uisession(), SIGNAL(sigAdditionsStateActualChange()), this, SLOT(sltAdditionsStateChanged()));
 }