--- stdcxx-4.2.1/include/rw/_config-gcc.h	2008-04-24 20:23:43.000000000 -0400
+++ stdcxx-4.2.1/include/rw/_config-gcc.h	2009-07-29 17:11:54.000000000 -0400
@@ -154,6 +154,18 @@
 
 #ifdef _RWSTD_OS_SUNOS
 
+// Solaris >= S10U6 on SPARC V8:
+// KU 137111-01 && CR 6296770
+// POSIX: pthread_mutex_t and pthread_condvar_t
+// Solaris: mutex_t and condvar_t MUST be aligned on
+// 8-byte boundary. 
+// This is relevant on 32-bit SPARCV8 only.
+// 64-bit SPARCV9 already aligns on 8-byte boundary by default.
+
+#  if defined(sparc) || defined(__sparc) || defined(__sparc__)
+#    define _RWSTD_STRICT_SPARCV8_MUTEX_ALIGNMENT 1
+#  endif // sparc || __sparc|| __sparc__
+
      // _SOLARIS_THREADS #defined when the -threads option is used on SunOS
 #  if defined (_SOLARIS_THREADS) && !defined (_RWSTD_SOLARIS_THREADS)
 #    define _RWSTD_SOLARIS_THREADS