diff --git a/allegro-4.2.0-nicevsync.patch b/allegro-4.2.0-nicevsync.patch
new file mode 100644
index 0000000..4424144
--- /dev/null
+++ b/allegro-4.2.0-nicevsync.patch
@@ -0,0 +1,10 @@
+--- allegro-4.2.0/src/x/xwin.c~	2006-03-21 12:57:42.000000000 +0100
++++ allegro-4.2.0/src/x/xwin.c	2006-03-21 12:57:42.000000000 +0100
+@@ -2265,6 +2265,7 @@
+       XUNLOCK();
+ 
+       do {
++         rest(1);
+       } while (retrace_count == prev);
+    }
+    else {
diff --git a/allegro.spec b/allegro.spec
index 628a974..084c0a7 100644
--- a/allegro.spec
+++ b/allegro.spec
@@ -1,6 +1,6 @@
 Name:           allegro
 Version:        4.2.0
-Release:        11
+Release:        12
 
 Summary:        A game programming library
 Summary(es):    Una libreria de programacion de juegos
@@ -21,6 +21,7 @@ Patch6:         allegro-4.2.0-64bit.patch
 Patch7:         allegro-4.2.0-fullscreen2.patch
 Patch8:         allegro-4.2.0-mprotect.patch
 Patch9:         allegro-4.2.0-no-execheap.patch
+Patch10:        allegro-4.2.0-nicevsync.patch
 BuildRoot:      %{_tmppath}/%{name}-%{version}-%{release}-root-%(%{__id_u} -n)
 BuildRequires:  esound-devel, texinfo, perl, arts-devel
 BuildRequires:  xorg-x11-proto-devel, libX11-devel, libXext-devel, libXt-devel
@@ -134,7 +135,7 @@ které jsou užitečné pro vývoj Allegro programů.
 %patch7 -p1 -z .fullscreen
 %patch8 -p1 -z .mprotect
 %patch9 -p1 -z .execheap
-
+%patch10 -p1 -z .nicevsync
 
 %build
 %configure \
@@ -221,6 +222,9 @@ rm -rf $RPM_BUILD_ROOT
 
 
 %changelog
+* Tue Mar 21 2006 Hans de Goede <j.w.r.degoede@hhs.nl> 4.2.0-12
+- Sleep in xwindows vsync emulation, instead of busy waiting.
+
 * Mon Mar 13 2006 Hans de Goede <j.w.r.degoede@hhs.nl> 4.2.0-11
 - really, _really_ fix asm stretch code on i386 with NX processors, long
   story see bugzilla bug 185214 .