diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 72ec96da4..9fb90b5ad 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,10 @@
+2011-03-20  Corinna Vinschen  <corinna@vinschen.de>
+
+	* fenv.cc (_feinitialise); Don't use SSE instructions on systems not
+	supporting them.
+	* wincap.h (wincaps::supports_sse): New element.
+	* wincap.cc: Implement above element throughout.
+
 2011-03-18  Corinna Vinschen  <corinna@vinschen.de>
 
 	* cygwin.sc: Raise default cygheap size to 2 Megs.
diff --git a/winsup/cygwin/fenv.cc b/winsup/cygwin/fenv.cc
index 63670f7ab..87466365a 100755
--- a/winsup/cygwin/fenv.cc
+++ b/winsup/cygwin/fenv.cc
@@ -1,6 +1,6 @@
 /* fenv.cc
 
-   Copyright 2010 Red Hat, Inc.
+   Copyright 2010, 2011 Red Hat, Inc.
 
 This file is part of Cygwin.
 
@@ -8,9 +8,11 @@ This software is a copyrighted work licensed under the terms of the
 Cygwin license.  Please consult the file "CYGWIN_LICENSE" for
 details. */
 
-#include <string.h>
+#include "winsup.h"
 #include "fenv.h"
 #include "errno.h"
+#include "wincap.h"
+#include <string.h>
 
 /*  Mask and shift amount for rounding bits.  */
 #define FE_CW_ROUND_MASK	(0x0c00)
@@ -419,8 +421,9 @@ _feinitialise (void)
   /* Check for presence of SSE: invoke CPUID #1, check EDX bit 25.  */
   eax = 1;
   __asm__ volatile ("cpuid" : "=d" (edx), "+a" (eax) :: "%ecx", "%ebx");
-  /* If this flag isn't set, we'll avoid trying to execute any SSE.  */
-  if (edx & (1 << 25))
+  /* If this flag isn't set, or if the OS doesn't support SSE (NT4, at least
+     up to SP4) we'll avoid trying to execute any SSE.  */
+  if ((edx & (1 << 25)) != 0 && wincap.supports_sse ())
     use_sse = true;
 
   /* Reset FPU: extended prec, all exceptions cleared and masked off.  */
diff --git a/winsup/cygwin/wincap.cc b/winsup/cygwin/wincap.cc
index c15372113..ee790eb63 100644
--- a/winsup/cygwin/wincap.cc
+++ b/winsup/cygwin/wincap.cc
@@ -63,6 +63,7 @@ wincaps wincap_nt4sp4 __attribute__((section (".cygwin_dll_common"), shared)) =
   has_restricted_raw_disk_access:false,
   use_dont_resolve_hack:false,
   use_get_sec_info_on_dirs:false,
+  supports_sse:false,
 };
 
 wincaps wincap_2000 __attribute__((section (".cygwin_dll_common"), shared)) = {
@@ -105,6 +106,7 @@ wincaps wincap_2000 __attribute__((section (".cygwin_dll_common"), shared)) = {
   has_restricted_raw_disk_access:false,
   use_dont_resolve_hack:false,
   use_get_sec_info_on_dirs:false,
+  supports_sse:true,
 };
 
 wincaps wincap_2000sp4 __attribute__((section (".cygwin_dll_common"), shared)) = {
@@ -147,6 +149,7 @@ wincaps wincap_2000sp4 __attribute__((section (".cygwin_dll_common"), shared)) =
   has_restricted_raw_disk_access:false,
   use_dont_resolve_hack:false,
   use_get_sec_info_on_dirs:false,
+  supports_sse:true,
 };
 
 wincaps wincap_xp __attribute__((section (".cygwin_dll_common"), shared)) = {
@@ -189,6 +192,7 @@ wincaps wincap_xp __attribute__((section (".cygwin_dll_common"), shared)) = {
   has_restricted_raw_disk_access:false,
   use_dont_resolve_hack:true,
   use_get_sec_info_on_dirs:true,
+  supports_sse:true,
 };
 
 wincaps wincap_xpsp1 __attribute__((section (".cygwin_dll_common"), shared)) = {
@@ -231,6 +235,7 @@ wincaps wincap_xpsp1 __attribute__((section (".cygwin_dll_common"), shared)) = {
   has_restricted_raw_disk_access:false,
   use_dont_resolve_hack:true,
   use_get_sec_info_on_dirs:true,
+  supports_sse:true,
 };
 
 wincaps wincap_xpsp2 __attribute__((section (".cygwin_dll_common"), shared)) = {
@@ -273,6 +278,7 @@ wincaps wincap_xpsp2 __attribute__((section (".cygwin_dll_common"), shared)) = {
   has_restricted_raw_disk_access:false,
   use_dont_resolve_hack:true,
   use_get_sec_info_on_dirs:true,
+  supports_sse:true,
 };
 
 wincaps wincap_2003 __attribute__((section (".cygwin_dll_common"), shared)) = {
@@ -315,6 +321,7 @@ wincaps wincap_2003 __attribute__((section (".cygwin_dll_common"), shared)) = {
   has_restricted_raw_disk_access:false,
   use_dont_resolve_hack:false,
   use_get_sec_info_on_dirs:true,
+  supports_sse:true,
 };
 
 wincaps wincap_vista __attribute__((section (".cygwin_dll_common"), shared)) = {
@@ -357,6 +364,7 @@ wincaps wincap_vista __attribute__((section (".cygwin_dll_common"), shared)) = {
   has_restricted_raw_disk_access:true,
   use_dont_resolve_hack:false,
   use_get_sec_info_on_dirs:false,
+  supports_sse:true,
 };
 
 wincaps wincap_7 __attribute__((section (".cygwin_dll_common"), shared)) = {
@@ -399,6 +407,7 @@ wincaps wincap_7 __attribute__((section (".cygwin_dll_common"), shared)) = {
   has_restricted_raw_disk_access:true,
   use_dont_resolve_hack:false,
   use_get_sec_info_on_dirs:false,
+  supports_sse:true,
 };
 
 wincapc wincap __attribute__((section (".cygwin_dll_common"), shared));
diff --git a/winsup/cygwin/wincap.h b/winsup/cygwin/wincap.h
index 60d051268..af86b1020 100644
--- a/winsup/cygwin/wincap.h
+++ b/winsup/cygwin/wincap.h
@@ -53,6 +53,7 @@ struct wincaps
   unsigned has_restricted_raw_disk_access		: 1;
   unsigned use_dont_resolve_hack			: 1;
   unsigned use_get_sec_info_on_dirs			: 1;
+  unsigned supports_sse					: 1;
 };
 
 class wincapc
@@ -111,6 +112,7 @@ public:
   bool	IMPLEMENT (has_restricted_raw_disk_access)
   bool	IMPLEMENT (use_dont_resolve_hack)
   bool	IMPLEMENT (use_get_sec_info_on_dirs)
+  bool	IMPLEMENT (supports_sse)
 
 #undef IMPLEMENT
 };