--- erts/configure.in.orig	2007-06-30 19:35:17.000000000 -0700
+++ erts/configure.in	2007-06-30 19:39:13.000000000 -0700
@@ -1697,6 +1697,13 @@
     __asm__ __volatile__("ldmxcsr %0" : : "m"(mxcsr));
 }
 
+#if defined(__DARWIN__)
+#include <mach/mach.h>
+#include <mach/machine/thread_status.h>
+#include <pthread.h>
+#endif
+
+
 #if defined(__x86_64__) || defined(__DARWIN__)
 static inline int cpu_has_sse2(void) { return 1; }
 #else /* !__x86_64__ */
@@ -1982,10 +1989,17 @@
     regs[PT_FPSCR] = 0x80|0x40|0x10;	/* VE, OE, ZE; not UE or XE */
 #endif
 #elif defined(__DARWIN__) && defined(__i386__)
+#if __DARWIN_UNIX03
+    mcontext_t mc = uc->uc_mcontext;
+    x86_float_state32_t *fpstate = &mc->__fs;
+    fpstate->__fpu_mxcsr = 0x1F80;
+    *(unsigned short *)&fpstate->__fpu_fsw &= ~0xFF;
+#else
     mcontext_t mc = uc->uc_mcontext;
     i386_float_state_t *fpstate = &mc->fs;
     fpstate->fpu_mxcsr = 0x1F80;
     *(unsigned short *)&fpstate->fpu_fsw &= ~0xFF;
+#endif
 #elif defined(__DARWIN__) && defined(__ppc__)
     mcontext_t mc = uc->uc_mcontext;
     mc->ss.srr0 += 4;