diff -ruN xfwm4-4.6.1/settings-dialogs/xfwm4-settings.c xfwm4-4.6.1-patched/settings-dialogs/xfwm4-settings.c
--- xfwm4-4.6.1/settings-dialogs/xfwm4-settings.c	2009-04-15 09:58:52.000000000 +0200
+++ xfwm4-4.6.1-patched/settings-dialogs/xfwm4-settings.c	2009-06-17 10:52:06.404079094 +0200
@@ -221,6 +221,8 @@
   { N_("Shade window"), "shade" },
   { N_("Hide window"), "hide" },
   { N_("Maximize window"), "maximize" },
+  { N_("Maximize window vertically"), "maximize-vertical" },
+  { N_("Maximize window horizontally"), "maximize-horizontal" },
   { N_("Fill window"), "fill" },
   { N_("Nothing"), "none" },
   { NULL, NULL }
diff -ruN xfwm4-4.6.1/src/events.c xfwm4-4.6.1-patched/src/events.c
--- xfwm4-4.6.1/src/events.c	2009-04-15 09:58:59.000000000 +0200
+++ xfwm4-4.6.1-patched/src/events.c	2009-06-17 10:48:50.227334599 +0200
@@ -757,6 +757,12 @@
             case DBL_CLICK_ACTION_MAXIMIZE:
                 clientToggleMaximized (c, WIN_STATE_MAXIMIZED, TRUE);
                 break;
+            case DBL_CLICK_ACTION_MAXIMIZE_VERTICAL:
+                clientToggleMaximized (c, WIN_STATE_MAXIMIZED_VERT, TRUE);
+                break;
+            case DBL_CLICK_ACTION_MAXIMIZE_HORIZONTAL:
+                clientToggleMaximized (c, WIN_STATE_MAXIMIZED_HORIZ, TRUE);
+                break;
             case DBL_CLICK_ACTION_SHADE:
                 clientToggleShaded (c);
                 break;
diff -ruN xfwm4-4.6.1/src/settings.c xfwm4-4.6.1-patched/src/settings.c
--- xfwm4-4.6.1/src/settings.c	2009-04-15 09:58:59.000000000 +0200
+++ xfwm4-4.6.1-patched/src/settings.c	2009-06-17 10:47:50.135081617 +0200
@@ -848,6 +848,14 @@
     {
         screen_info->params->double_click_action = DBL_CLICK_ACTION_MAXIMIZE;
     }
+    else if (!g_ascii_strcasecmp ("maximize-vertical", value))
+    {
+        screen_info->params->double_click_action = DBL_CLICK_ACTION_MAXIMIZE_VERTICAL;
+    }
+    else if (!g_ascii_strcasecmp ("maximize-horizontal", value))
+    {
+        screen_info->params->double_click_action = DBL_CLICK_ACTION_MAXIMIZE_HORIZONTAL;
+    }
     else if (!g_ascii_strcasecmp ("fill", value))
     {
         screen_info->params->double_click_action = DBL_CLICK_ACTION_FILL;
diff -ruN xfwm4-4.6.1/src/settings.h xfwm4-4.6.1-patched/src/settings.h
--- xfwm4-4.6.1/src/settings.h	2009-04-15 09:58:59.000000000 +0200
+++ xfwm4-4.6.1-patched/src/settings.h	2009-06-17 10:47:11.048086902 +0200
@@ -135,7 +135,9 @@
     DBL_CLICK_ACTION_MAXIMIZE,
     DBL_CLICK_ACTION_SHADE,
     DBL_CLICK_ACTION_FILL,
-    DBL_CLICK_ACTION_HIDE
+    DBL_CLICK_ACTION_HIDE,
+    DBL_CLICK_ACTION_MAXIMIZE_VERTICAL,
+    DBL_CLICK_ACTION_MAXIMIZE_HORIZONTAL
 };
 
 enum