diff --git a/src/gui.c b/src/gui.c
index c25f760..48e7b0f 100644
--- a/src/gui.c
+++ b/src/gui.c
@@ -1386,6 +1386,10 @@
     int		min_height;
     int		screen_w;
     int		screen_h;
+#ifdef HAVE_GTK2
+    int		un_maximize = mustset;
+    int         did_adjust = 0;
+#endif
 
     if (!gui.shell_created)
 	return;
@@ -1425,22 +1429,47 @@
 	    if (Columns < MIN_COLUMNS)
 		Columns = MIN_COLUMNS;
 	    width = Columns * gui.char_width + base_width;
+#ifdef HAVE_GTK2
+	    ++did_adjust;
+#endif
 	}
 	if ((direction & RESIZE_VERT) && height > screen_h)
 	{
 	    Rows = (screen_h - base_height) / gui.char_height;
 	    check_shellsize();
 	    height = Rows * gui.char_height + base_height;
+#ifdef HAVE_GTK2
+	    ++did_adjust;
+#endif
 	}
+#ifdef HAVE_GTK2
+	if (did_adjust == 2 || (width + gui.char_width >= screen_w
+				     && height + gui.char_height >= screen_h))
+	    /* don't unmaximize if at maximum size */
+	    un_maximize = FALSE;
+#endif
     }
     gui.num_cols = Columns;
     gui.num_rows = Rows;
 
     min_width = base_width + MIN_COLUMNS * gui.char_width;
     min_height = base_height + MIN_LINES * gui.char_height;
-# ifdef FEAT_WINDOWS
+#ifdef FEAT_WINDOWS
     min_height += tabline_height() * gui.char_height;
-# endif
+#endif
+
+#ifdef HAVE_GTK2
+    if (un_maximize)
+    {
+	/* If the window size is smaller than the screen unmaximize the
+	 * window, otherwise resizing won't work. */
+	gui_mch_get_screen_dimensions(&screen_w, &screen_h);
+	if ((width + gui.char_width < screen_w
+				   || height + gui.char_height * 2 < screen_h)
+		&& gui_mch_maximized())
+	    gui_mch_unmaximize();
+    }
+#endif
 
     gui_mch_set_shellsize(width, height, min_width, min_height,
 					  base_width, base_height, direction);
diff --git a/src/gui_gtk_x11.c b/src/gui_gtk_x11.c
index cb50d03..ad6fc25 100644
--- a/src/gui_gtk_x11.c
+++ b/src/gui_gtk_x11.c
@@ -4376,6 +4376,29 @@
 #endif
 #endif /* HAVE_GTK2 */
 
+#if defined(HAVE_GTK2) || defined(PROTO)
+/*
+ * Return TRUE if the main window is maximized.
+ */
+    int
+gui_mch_maximized()
+{
+    return (gui.mainwin != NULL && gui.mainwin->window != NULL
+	    && (gdk_window_get_state(gui.mainwin->window)
+					       & GDK_WINDOW_STATE_MAXIMIZED));
+}
+
+/*
+ * Unmaximize the main window
+ */
+    void
+gui_mch_unmaximize()
+{
+    if (gui.mainwin != NULL)
+	gtk_window_unmaximize(GTK_WINDOW(gui.mainwin));
+}
+#endif
+
 /*
  * Set the windows size.
  */
diff --git a/src/proto/gui_gtk_x11.pro b/src/proto/gui_gtk_x11.pro
index 87ff6da..93b65bf 100644
--- a/src/proto/gui_gtk_x11.pro
+++ b/src/proto/gui_gtk_x11.pro
@@ -16,6 +16,8 @@
 void gui_mch_exit __ARGS((int rc));
 int gui_mch_get_winpos __ARGS((int *x, int *y));
 void gui_mch_set_winpos __ARGS((int x, int y));
+int gui_mch_maximized __ARGS((void));
+void gui_mch_unmaximize __ARGS((void));
 void gui_mch_set_shellsize __ARGS((int width, int height, int min_width, int min_height, int base_width, int base_height, int direction));
 void gui_mch_get_screen_dimensions __ARGS((int *screen_w, int *screen_h));
 void gui_mch_settitle __ARGS((char_u *title, char_u *icon));
diff --git a/src/version.c b/src/version.c
index 1f3f201..3633057 100644
--- a/src/version.c
+++ b/src/version.c
@@ -677,6 +677,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    264,
+/**/
     263,
 /**/
     262,