--- a/target-i386/translate.c	2011-06-03 16:17:18.270208646 +0100
+++ b/target-i386/translate.c	2011-06-03 16:02:41.381556714 +0100
@@ -7560,7 +7560,7 @@
             break;
         case 5: /* lfence */
         case 6: /* mfence */
-            if ((modrm & 0xc7) != 0xc0 || !(s->cpuid_features & CPUID_SSE))
+            if ((modrm & 0xc7) != 0xc0 || !(s->cpuid_features & CPUID_SSE2))
                 goto illegal_op;
             break;
         case 7: /* sfence / clflush */