--- cacao-0.99.4.orig/src/cacaoh/headers.c	2008-08-04 18:51:28.000000000 +0200
+++ cacao-0.99.4/src/cacaoh/headers.c	2011-03-26 20:11:11.000000000 +0100
@@ -35,8 +35,10 @@
 #if defined(ENABLE_THREADS)
 # if defined(__DARWIN__)
 #  include <signal.h>
+#  include <sys/ucontext.h>
+# else
+#  include <ucontext.h>
 # endif
-# include <ucontext.h>
 #endif
 
 #include "mm/gc-common.h"