Index: /trunk/ccl/lisp-kernel/x86-exceptions.h
===================================================================
--- /trunk/ccl/lisp-kernel/x86-exceptions.h	(revision 5007)
+++ /trunk/ccl/lisp-kernel/x86-exceptions.h	(revision 5008)
@@ -28,4 +28,6 @@
 
 #ifdef DARWIN
+/* DarwinSigReturn works around an old G5 bug */
+#define DarwinSigReturn(context)
 #ifdef X8664
 #define xpGPRvector(x) ((natural *)(&(UC_MCONTEXT(x)->ss.rax)))
@@ -126,5 +128,5 @@
 #ifdef DARWIN
 #define SIGNUM_FOR_INTN_TRAP SIGSEGV /* Not really, but our Mach handler fakes that */
-#define IS_MAYBE_INT_TRAP(info,xp) 0 /* Fix this */
+#define IS_MAYBE_INT_TRAP(info,xp) (info->si_code == EXC_I386_GPFLT)
 #define SIGRETURN(context)
 #endif