diff -up dwm-6.0/config.def.h dwm-6.0-focusonclick/config.def.h
--- dwm-6.0/config.def.h	2011-12-19 09:02:46.000000000 -0600
+++ dwm-6.0-focusonclick/config.def.h	2012-11-24 17:48:19.867072611 -0600
@@ -13,6 +13,9 @@ static const unsigned int snap      = 32
 static const Bool showbar           = True;     /* False means no bar */
 static const Bool topbar            = True;     /* False means bottom bar */
 
+/* False means using the scroll wheel on a window will not change focus */
+static const Bool focusonwheelscroll = False;
+
 /* tagging */
 static const char *tags[] = { "1", "2", "3", "4", "5", "6", "7", "8", "9" };
 
diff -up dwm-6.0/dwm.c dwm-6.0-focusonclick/dwm.c
--- dwm-6.0/dwm.c	2011-12-19 09:02:46.000000000 -0600
+++ dwm-6.0-focusonclick/dwm.c	2012-11-24 18:00:08.902254102 -0600
@@ -266,7 +266,6 @@ static void (*handler[LASTEvent]) (XEven
 	[ConfigureRequest] = configurerequest,
 	[ConfigureNotify] = configurenotify,
 	[DestroyNotify] = destroynotify,
-	[EnterNotify] = enternotify,
 	[Expose] = expose,
 	[FocusIn] = focusin,
 	[KeyPress] = keypress,
@@ -455,7 +454,9 @@ buttonpress(XEvent *e) {
 			click = ClkWinTitle;
 	}
 	else if((c = wintoclient(ev->window))) {
-		focus(c);
+		if (focusonwheelscroll || (ev->button != Button4 && ev->button != Button5))
+			focus(c);
+		XAllowEvents(dpy, ReplayPointer, CurrentTime);
 		click = ClkClientWin;
 	}
 	for(i = 0; i < LENGTH(buttons); i++)
@@ -1001,11 +1002,11 @@ grabbuttons(Client *c, Bool focused) {
 						XGrabButton(dpy, buttons[i].button,
 						            buttons[i].mask | modifiers[j],
 						            c->win, False, BUTTONMASK,
-						            GrabModeAsync, GrabModeSync, None, None);
+						            GrabModeSync, GrabModeSync, None, None);
 		}
 		else
 			XGrabButton(dpy, AnyButton, AnyModifier, c->win, False,
-			            BUTTONMASK, GrabModeAsync, GrabModeSync, None, None);
+			            BUTTONMASK, GrabModeSync, GrabModeSync, None, None);
 	}
 }