diff --git a/include/Mw/LowLevel/X11.h b/include/Mw/LowLevel/X11.h
index ab9c43d..ec36c04 100644
--- a/include/Mw/LowLevel/X11.h
+++ b/include/Mw/LowLevel/X11.h
@@ -29,6 +29,7 @@ struct _MwLLX11 {
 	GC	 gc;
 	Colormap colormap;
 	Atom	 wm_delete;
+	Atom	 wm_protocols;
 	XIM	 xim;
 	XIC	 xic;
 
diff --git a/src/backend/x11.c b/src/backend/x11.c
index c44daaf..0353a24 100644
--- a/src/backend/x11.c
+++ b/src/backend/x11.c
@@ -209,8 +209,9 @@ static MwLL MwLLCreateImpl(MwLL parent, int x, int y, int width, int height) {
 	r->x11.grabbed	    = 0;
 	r->x11.force_render = 0;
 
-	r->x11.colormap	 = DefaultColormap(r->x11.display, XDefaultScreen(r->x11.display));
-	r->x11.wm_delete = XInternAtom(r->x11.display, "WM_DELETE_WINDOW", False);
+	r->x11.colormap	    = DefaultColormap(r->x11.display, XDefaultScreen(r->x11.display));
+	r->x11.wm_delete    = XInternAtom(r->x11.display, "WM_DELETE_WINDOW", False);
+	r->x11.wm_protocols = XInternAtom(r->x11.display, "WM_PROTOCOLS", False);
 	XSetWMProtocols(r->x11.display, r->x11.window, &r->x11.wm_delete, 1);
 
 	r->x11.gc = XCreateGC(r->x11.display, r->x11.window, 0, NULL);
@@ -471,7 +472,7 @@ static void MwLLNextEventImpl(MwLL handle) {
 			handle->x11.width  = ev.xconfigure.width;
 			handle->x11.height = ev.xconfigure.height;
 		} else if(ev.type == ClientMessage) {
-			if(ev.xclient.data.l[0] == (long)handle->x11.wm_delete) {
+			if(ev.xclient.message_type == handle->x11.wm_protocols && ev.xclient.data.l[0] == (long)handle->x11.wm_delete) {
 				MwLLDispatch(handle, close, NULL);
 			}
 		} else if(ev.type == FocusIn) {