diff --git a/modules/plugin/base/src/ns4xPluginInstance.cpp b/modules/plugin/base/src/ns4xPluginInstance.cpp
index 4595c1ad3122..5ef8c6780017 100644
--- a/modules/plugin/base/src/ns4xPluginInstance.cpp
+++ b/modules/plugin/base/src/ns4xPluginInstance.cpp
@@ -998,6 +998,7 @@ NS_IMETHODIMP ns4xPluginInstance::SetWindow(nsPluginWindow* window)
   // to the actual X window
   window->window = (nsPluginPort *)GTK_XTBIN(mXtBin)->xtwindow;
   
+  gtk_xtbin_resize(mXtBin, window->width, window->height);
   
 #elif defined(MOZ_WIDGET_XLIB)
 
diff --git a/widget/src/gtkxtbin/gtkxtbin.c b/widget/src/gtkxtbin/gtkxtbin.c
index ed1e0ea08d45..ff5f916eeab0 100644
--- a/widget/src/gtkxtbin/gtkxtbin.c
+++ b/widget/src/gtkxtbin/gtkxtbin.c
@@ -451,6 +451,19 @@ gtk_xtbin_set_position (GtkXtBin *xtbin,
     gdk_window_move (GTK_WIDGET (xtbin)->window, x, y);
 }
 
+void
+gtk_xtbin_resize (GtkWidget *widget,
+                  gint       width,
+                  gint       height)
+{
+  Arg args[2];
+  GtkXtBin *xtbin = GTK_XTBIN (widget);
+  Widget xtwidget = XtWindowToWidget(xtbin->xtdisplay, xtbin->xtwindow);
+
+  XtSetArg(args[0], XtNheight, height);
+  XtSetArg(args[1], XtNwidth,  width);
+  XtSetValues(XtParent(xtwidget), args, 2);
+}
 
 static void
 gtk_xtbin_shutdown (GtkObject *object)
diff --git a/widget/src/gtkxtbin/gtkxtbin.h b/widget/src/gtkxtbin/gtkxtbin.h
index 00fa56cb512f..ec7e4d5c59b4 100644
--- a/widget/src/gtkxtbin/gtkxtbin.h
+++ b/widget/src/gtkxtbin/gtkxtbin.h
@@ -66,6 +66,9 @@ GtkWidget *gtk_xtbin_new (GdkWindow *parent_window, String *f);
 void       gtk_xtbin_set_position (GtkXtBin *xtbin,
                                    gint       x,
                                    gint       y);
+void       gtk_xtbin_resize (GtkWidget *widget,
+                             gint       width,
+                             gint       height);
 
 typedef struct _XtTMRec {
     XtTranslations  translations;       /* private to Translation Manager    */