diff --git a/Misc/NEWS b/Misc/NEWS
index 55ebfa5..13ffc04 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -926,6 +926,8 @@
 Build
 -----
 
+- Define _BSD_SOURCE, to get access to POSIX extensions on OpenBSD 4.1+.
+
 - Stop supporting AtheOS and cause a build error in configure for the platform.
 
 - Bug #1655392: don't add -L/usr/lib/pythonX.Y/config to the LDFLAGS
diff --git a/configure b/configure
index 507b720..6212243 100755
--- a/configure
+++ b/configure
@@ -1,5 +1,5 @@
 #! /bin/sh
-# From configure.in Revision: 54283 .
+# From configure.in Revision: 55739 .
 # Guess values for system-dependent variables and create Makefiles.
 # Generated by GNU Autoconf 2.61 for python 2.6.
 #
@@ -1838,6 +1838,14 @@
 _ACEOF
 
 
+# OpenBSD undoes our definition of __BSD_VISIBLE if _XOPEN_SOURCE is
+# also defined. This can be overridden by defining _BSD_SOURCE
+
+cat >>confdefs.h <<\_ACEOF
+#define _BSD_SOURCE 1
+_ACEOF
+
+
 # The later defininition of _XOPEN_SOURCE and _POSIX_C_SOURCE disables
 # u_int on Irix 5.3. Defining _BSD_TYPES brings it back.
 
diff --git a/configure.in b/configure.in
index 2809813..4b3e03d 100644
--- a/configure.in
+++ b/configure.in
@@ -50,6 +50,10 @@
 # them.
 AC_DEFINE(__BSD_VISIBLE, 1, [Define on FreeBSD to activate all library features])
 
+# OpenBSD undoes our definition of __BSD_VISIBLE if _XOPEN_SOURCE is
+# also defined. This can be overridden by defining _BSD_SOURCE
+AC_DEFINE(_BSD_SOURCE, 1, [Define on OpenBSD to activate all library features])
+
 # The later defininition of _XOPEN_SOURCE and _POSIX_C_SOURCE disables
 # u_int on Irix 5.3. Defining _BSD_TYPES brings it back.
 AC_DEFINE(_BSD_TYPES, 1, [Define on Irix to enable u_int])
diff --git a/pyconfig.h.in b/pyconfig.h.in
index d5dafc1..012bf7e 100644
--- a/pyconfig.h.in
+++ b/pyconfig.h.in
@@ -103,6 +103,10 @@
 /* Define if you have the 'resize_term' function. */
 #undef HAVE_CURSES_RESIZE_TERM
 
+/* Define to 1 if you have the declaration of `tzname', and to 0 if you don't.
+   */
+#undef HAVE_DECL_TZNAME
+
 /* Define to 1 if you have the device macros. */
 #undef HAVE_DEVICE_MACROS
 
@@ -802,22 +806,22 @@
 /* Define if i>>j for signed int i does not extend the sign bit when i < 0 */
 #undef SIGNED_RIGHT_SHIFT_ZERO_FILLS
 
-/* The size of a `double', as computed by sizeof. */
+/* The size of `double', as computed by sizeof. */
 #undef SIZEOF_DOUBLE
 
-/* The size of a `float', as computed by sizeof. */
+/* The size of `float', as computed by sizeof. */
 #undef SIZEOF_FLOAT
 
-/* The size of a `fpos_t', as computed by sizeof. */
+/* The size of `fpos_t', as computed by sizeof. */
 #undef SIZEOF_FPOS_T
 
-/* The size of a `int', as computed by sizeof. */
+/* The size of `int', as computed by sizeof. */
 #undef SIZEOF_INT
 
-/* The size of a `long', as computed by sizeof. */
+/* The size of `long', as computed by sizeof. */
 #undef SIZEOF_LONG
 
-/* The size of a `long long', as computed by sizeof. */
+/* The size of `long long', as computed by sizeof. */
 #undef SIZEOF_LONG_LONG
 
 /* The number of bytes in an off_t. */
@@ -826,25 +830,25 @@
 /* The number of bytes in a pthread_t. */
 #undef SIZEOF_PTHREAD_T
 
-/* The size of a `short', as computed by sizeof. */
+/* The size of `short', as computed by sizeof. */
 #undef SIZEOF_SHORT
 
-/* The size of a `size_t', as computed by sizeof. */
+/* The size of `size_t', as computed by sizeof. */
 #undef SIZEOF_SIZE_T
 
 /* The number of bytes in a time_t. */
 #undef SIZEOF_TIME_T
 
-/* The size of a `uintptr_t', as computed by sizeof. */
+/* The size of `uintptr_t', as computed by sizeof. */
 #undef SIZEOF_UINTPTR_T
 
-/* The size of a `void *', as computed by sizeof. */
+/* The size of `void *', as computed by sizeof. */
 #undef SIZEOF_VOID_P
 
-/* The size of a `wchar_t', as computed by sizeof. */
+/* The size of `wchar_t', as computed by sizeof. */
 #undef SIZEOF_WCHAR_T
 
-/* The size of a `_Bool', as computed by sizeof. */
+/* The size of `_Bool', as computed by sizeof. */
 #undef SIZEOF__BOOL
 
 /* Define to 1 if you have the ANSI C header files. */
@@ -924,6 +928,9 @@
 # undef _ALL_SOURCE
 #endif
 
+/* Define on OpenBSD to activate all library features */
+#undef _BSD_SOURCE
+
 /* Define on Irix to enable u_int */
 #undef _BSD_TYPES
 
@@ -980,7 +987,7 @@
 /* Define to `int' if <sys/types.h> does not define. */
 #undef mode_t
 
-/* Define to `long' if <sys/types.h> does not define. */
+/* Define to `long int' if <sys/types.h> does not define. */
 #undef off_t
 
 /* Define to `int' if <sys/types.h> does not define. */
@@ -989,7 +996,7 @@
 /* Define to empty if the keyword does not work. */
 #undef signed
 
-/* Define to `unsigned' if <sys/types.h> does not define. */
+/* Define to `unsigned int' if <sys/types.h> does not define. */
 #undef size_t
 
 /* Define to `int' if <sys/socket.h> does not define. */