diff -up ilmbase-2.0.1/IexMath/IexMathFpu.cpp.orig ilmbase-2.0.1/IexMath/IexMathFpu.cpp
--- ilmbase-2.0.1/IexMath/IexMathFpu.cpp.orig	2013-06-18 14:51:38.000000000 -0500
+++ ilmbase-2.0.1/IexMath/IexMathFpu.cpp	2013-09-08 17:40:19.116158714 -0500
@@ -53,7 +53,7 @@
 #endif
 
 
-#ifdef HAVE_UCONTEXT_H
+#if defined(HAVE_UCONTEXT_H) && (defined(__x86_64__) || defined(__i386__))
 
 
 #include <ucontext.h>