diff --git a/configure b/configure
index 5d669b4a19..73fa5e4b6c 100755
--- a/configure
+++ b/configure
@@ -3472,6 +3472,9 @@ fi;
 
 
 
+#
+# Elf
+#
 
 # Assume system is ELF if it predefines __ELF__ as 1,
 # otherwise believe host_os based default.
@@ -3503,7 +3506,336 @@ rm -f conftest*
 
 
 
+#
+# Pthreads
+#
 
+echo "$as_me:$LINENO: checking for ANSI C header files" >&5
+echo $ECHO_N "checking for ANSI C header files... $ECHO_C" >&6
+if test "${ac_cv_header_stdc+set}" = set; then
+  echo $ECHO_N "(cached) $ECHO_C" >&6
+else
+  cat >conftest.$ac_ext <<_ACEOF
+#line $LINENO "configure"
+#include "confdefs.h"
+#include <stdlib.h>
+#include <stdarg.h>
+#include <string.h>
+#include <float.h>
+
+_ACEOF
+if { (eval echo "$as_me:$LINENO: \"$ac_cpp conftest.$ac_ext\"") >&5
+  (eval $ac_cpp conftest.$ac_ext) 2>conftest.er1
+  ac_status=$?
+  egrep -v '^ *\+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } >/dev/null; then
+  if test -s conftest.err; then
+    ac_cpp_err=$ac_c_preproc_warn_flag
+  else
+    ac_cpp_err=
+  fi
+else
+  ac_cpp_err=yes
+fi
+if test -z "$ac_cpp_err"; then
+  ac_cv_header_stdc=yes
+else
+  echo "$as_me: failed program was:" >&5
+  cat conftest.$ac_ext >&5
+  ac_cv_header_stdc=no
+fi
+rm -f conftest.err conftest.$ac_ext
+
+if test $ac_cv_header_stdc = yes; then
+  # SunOS 4.x string.h does not declare mem*, contrary to ANSI.
+  cat >conftest.$ac_ext <<_ACEOF
+#line $LINENO "configure"
+#include "confdefs.h"
+#include <string.h>
+
+_ACEOF
+if (eval "$ac_cpp conftest.$ac_ext") 2>&5 |
+  egrep "memchr" >/dev/null 2>&1; then
+  :
+else
+  ac_cv_header_stdc=no
+fi
+rm -f conftest*
+
+fi
+
+if test $ac_cv_header_stdc = yes; then
+  # ISC 2.0.2 stdlib.h does not declare free, contrary to ANSI.
+  cat >conftest.$ac_ext <<_ACEOF
+#line $LINENO "configure"
+#include "confdefs.h"
+#include <stdlib.h>
+
+_ACEOF
+if (eval "$ac_cpp conftest.$ac_ext") 2>&5 |
+  egrep "free" >/dev/null 2>&1; then
+  :
+else
+  ac_cv_header_stdc=no
+fi
+rm -f conftest*
+
+fi
+
+if test $ac_cv_header_stdc = yes; then
+  # /bin/cc in Irix-4.0.5 gets non-ANSI ctype macros unless using -ansi.
+  if test "$cross_compiling" = yes; then
+  :
+else
+  cat >conftest.$ac_ext <<_ACEOF
+#line $LINENO "configure"
+#include "confdefs.h"
+#include <ctype.h>
+#if ((' ' & 0x0FF) == 0x020)
+# define ISLOWER(c) ('a' <= (c) && (c) <= 'z')
+# define TOUPPER(c) (ISLOWER(c) ? 'A' + ((c) - 'a') : (c))
+#else
+# define ISLOWER(c) (('a' <= (c) && (c) <= 'i') \
+                     || ('j' <= (c) && (c) <= 'r') \
+                     || ('s' <= (c) && (c) <= 'z'))
+# define TOUPPER(c) (ISLOWER(c) ? ((c) | 0x40) : (c))
+#endif
+
+#define XOR(e, f) (((e) && !(f)) || (!(e) && (f)))
+int
+main ()
+{
+  int i;
+  for (i = 0; i < 256; i++)
+    if (XOR (islower (i), ISLOWER (i))
+        || toupper (i) != TOUPPER (i))
+      exit(2);
+  exit (0);
+}
+_ACEOF
+rm -f conftest$ac_exeext
+if { (eval echo "$as_me:$LINENO: \"$ac_link\"") >&5
+  (eval $ac_link) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } && { ac_try='./conftest$ac_exeext'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+  :
+else
+  echo "$as_me: program exited with status $ac_status" >&5
+echo "$as_me: failed program was:" >&5
+cat conftest.$ac_ext >&5
+( exit $ac_status )
+ac_cv_header_stdc=no
+fi
+rm -f core core.* *.core conftest$ac_exeext conftest.$ac_objext conftest.$ac_ext
+fi
+fi
+fi
+echo "$as_me:$LINENO: result: $ac_cv_header_stdc" >&5
+echo "${ECHO_T}$ac_cv_header_stdc" >&6
+if test $ac_cv_header_stdc = yes; then
+
+cat >>confdefs.h <<\_ACEOF
+#define STDC_HEADERS 1
+_ACEOF
+
+fi
+
+# On IRIX 5.3, sys/types and inttypes.h are conflicting.
+
+
+
+
+
+
+
+
+
+for ac_header in sys/types.h sys/stat.h stdlib.h string.h memory.h strings.h \
+                  inttypes.h stdint.h unistd.h
+do
+as_ac_Header=`echo "ac_cv_header_$ac_header" | $as_tr_sh`
+echo "$as_me:$LINENO: checking for $ac_header" >&5
+echo $ECHO_N "checking for $ac_header... $ECHO_C" >&6
+if eval "test \"\${$as_ac_Header+set}\" = set"; then
+  echo $ECHO_N "(cached) $ECHO_C" >&6
+else
+  cat >conftest.$ac_ext <<_ACEOF
+#line $LINENO "configure"
+#include "confdefs.h"
+$ac_includes_default
+
+#include <$ac_header>
+_ACEOF
+rm -f conftest.$ac_objext
+if { (eval echo "$as_me:$LINENO: \"$ac_compile\"") >&5
+  (eval $ac_compile) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } &&
+         { ac_try='test -s conftest.$ac_objext'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+  eval "$as_ac_Header=yes"
+else
+  echo "$as_me: failed program was:" >&5
+cat conftest.$ac_ext >&5
+eval "$as_ac_Header=no"
+fi
+rm -f conftest.$ac_objext conftest.$ac_ext
+fi
+echo "$as_me:$LINENO: result: `eval echo '${'$as_ac_Header'}'`" >&5
+echo "${ECHO_T}`eval echo '${'$as_ac_Header'}'`" >&6
+if test `eval echo '${'$as_ac_Header'}'` = yes; then
+  cat >>confdefs.h <<_ACEOF
+#define `echo "HAVE_$ac_header" | $as_tr_cpp` 1
+_ACEOF
+
+fi
+
+done
+
+
+if test "${ac_cv_header_pthread_h+set}" = set; then
+  echo "$as_me:$LINENO: checking for pthread.h" >&5
+echo $ECHO_N "checking for pthread.h... $ECHO_C" >&6
+if test "${ac_cv_header_pthread_h+set}" = set; then
+  echo $ECHO_N "(cached) $ECHO_C" >&6
+fi
+echo "$as_me:$LINENO: result: $ac_cv_header_pthread_h" >&5
+echo "${ECHO_T}$ac_cv_header_pthread_h" >&6
+else
+  # Is the header compilable?
+echo "$as_me:$LINENO: checking pthread.h usability" >&5
+echo $ECHO_N "checking pthread.h usability... $ECHO_C" >&6
+cat >conftest.$ac_ext <<_ACEOF
+#line $LINENO "configure"
+#include "confdefs.h"
+$ac_includes_default
+#include <pthread.h>
+_ACEOF
+rm -f conftest.$ac_objext
+if { (eval echo "$as_me:$LINENO: \"$ac_compile\"") >&5
+  (eval $ac_compile) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } &&
+         { ac_try='test -s conftest.$ac_objext'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+  ac_header_compiler=yes
+else
+  echo "$as_me: failed program was:" >&5
+cat conftest.$ac_ext >&5
+ac_header_compiler=no
+fi
+rm -f conftest.$ac_objext conftest.$ac_ext
+echo "$as_me:$LINENO: result: $ac_header_compiler" >&5
+echo "${ECHO_T}$ac_header_compiler" >&6
+
+# Is the header present?
+echo "$as_me:$LINENO: checking pthread.h presence" >&5
+echo $ECHO_N "checking pthread.h presence... $ECHO_C" >&6
+cat >conftest.$ac_ext <<_ACEOF
+#line $LINENO "configure"
+#include "confdefs.h"
+#include <pthread.h>
+_ACEOF
+if { (eval echo "$as_me:$LINENO: \"$ac_cpp conftest.$ac_ext\"") >&5
+  (eval $ac_cpp conftest.$ac_ext) 2>conftest.er1
+  ac_status=$?
+  egrep -v '^ *\+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } >/dev/null; then
+  if test -s conftest.err; then
+    ac_cpp_err=$ac_c_preproc_warn_flag
+  else
+    ac_cpp_err=
+  fi
+else
+  ac_cpp_err=yes
+fi
+if test -z "$ac_cpp_err"; then
+  ac_header_preproc=yes
+else
+  echo "$as_me: failed program was:" >&5
+  cat conftest.$ac_ext >&5
+  ac_header_preproc=no
+fi
+rm -f conftest.err conftest.$ac_ext
+echo "$as_me:$LINENO: result: $ac_header_preproc" >&5
+echo "${ECHO_T}$ac_header_preproc" >&6
+
+# So?  What about this header?
+case $ac_header_compiler:$ac_header_preproc in
+  yes:no )
+    { echo "$as_me:$LINENO: WARNING: pthread.h: accepted by the compiler, rejected by the preprocessor!" >&5
+echo "$as_me: WARNING: pthread.h: accepted by the compiler, rejected by the preprocessor!" >&2;}
+    { echo "$as_me:$LINENO: WARNING: pthread.h: proceeding with the preprocessor's result" >&5
+echo "$as_me: WARNING: pthread.h: proceeding with the preprocessor's result" >&2;};;
+  no:yes )
+    { echo "$as_me:$LINENO: WARNING: pthread.h: present but cannot be compiled" >&5
+echo "$as_me: WARNING: pthread.h: present but cannot be compiled" >&2;}
+    { echo "$as_me:$LINENO: WARNING: pthread.h: check for missing prerequisite headers?" >&5
+echo "$as_me: WARNING: pthread.h: check for missing prerequisite headers?" >&2;}
+    { echo "$as_me:$LINENO: WARNING: pthread.h: proceeding with the preprocessor's result" >&5
+echo "$as_me: WARNING: pthread.h: proceeding with the preprocessor's result" >&2;};;
+esac
+echo "$as_me:$LINENO: checking for pthread.h" >&5
+echo $ECHO_N "checking for pthread.h... $ECHO_C" >&6
+if test "${ac_cv_header_pthread_h+set}" = set; then
+  echo $ECHO_N "(cached) $ECHO_C" >&6
+else
+  ac_cv_header_pthread_h=$ac_header_preproc
+fi
+echo "$as_me:$LINENO: result: $ac_cv_header_pthread_h" >&5
+echo "${ECHO_T}$ac_cv_header_pthread_h" >&6
+
+fi
+if test $ac_cv_header_pthread_h = yes; then
+
+cat >>confdefs.h <<\_ACEOF
+#define HAVE_THREADS 1
+_ACEOF
+
+fi
+
+
+if test ! -z "$HAVE_THREADS"
+then
+	case $host_os in
+		# BSD/OS and NetBSD require no special libraries or flags
+		netbsd*|bsdi*) ;;
+		freebsd2*|freebsd3*|freebsd4*) THREAD_CFLAGS="-pthread" ;;
+		freebsd*) THREAD_LIBS="-lc_r" ;;
+		linux*) THREAD_LIBS="-lpthread"
+			THREAD_CFLAGS="-D_REENTRANT" ;;
+	# other operating systems might fail because they have pthread.h but need
+	# special libs we don't know about yet.
+	esac
+fi
+
+
+
+#
+# Assignments
+#
 
 CPPFLAGS="$CPPFLAGS $INCLUDES"
 LDFLAGS="$LDFLAGS $LIBDIRS"
@@ -6768,203 +7100,6 @@ fi
 ## Header files
 ##
 
-echo "$as_me:$LINENO: checking for ANSI C header files" >&5
-echo $ECHO_N "checking for ANSI C header files... $ECHO_C" >&6
-if test "${ac_cv_header_stdc+set}" = set; then
-  echo $ECHO_N "(cached) $ECHO_C" >&6
-else
-  cat >conftest.$ac_ext <<_ACEOF
-#line $LINENO "configure"
-#include "confdefs.h"
-#include <stdlib.h>
-#include <stdarg.h>
-#include <string.h>
-#include <float.h>
-
-_ACEOF
-if { (eval echo "$as_me:$LINENO: \"$ac_cpp conftest.$ac_ext\"") >&5
-  (eval $ac_cpp conftest.$ac_ext) 2>conftest.er1
-  ac_status=$?
-  egrep -v '^ *\+' conftest.er1 >conftest.err
-  rm -f conftest.er1
-  cat conftest.err >&5
-  echo "$as_me:$LINENO: \$? = $ac_status" >&5
-  (exit $ac_status); } >/dev/null; then
-  if test -s conftest.err; then
-    ac_cpp_err=$ac_c_preproc_warn_flag
-  else
-    ac_cpp_err=
-  fi
-else
-  ac_cpp_err=yes
-fi
-if test -z "$ac_cpp_err"; then
-  ac_cv_header_stdc=yes
-else
-  echo "$as_me: failed program was:" >&5
-  cat conftest.$ac_ext >&5
-  ac_cv_header_stdc=no
-fi
-rm -f conftest.err conftest.$ac_ext
-
-if test $ac_cv_header_stdc = yes; then
-  # SunOS 4.x string.h does not declare mem*, contrary to ANSI.
-  cat >conftest.$ac_ext <<_ACEOF
-#line $LINENO "configure"
-#include "confdefs.h"
-#include <string.h>
-
-_ACEOF
-if (eval "$ac_cpp conftest.$ac_ext") 2>&5 |
-  egrep "memchr" >/dev/null 2>&1; then
-  :
-else
-  ac_cv_header_stdc=no
-fi
-rm -f conftest*
-
-fi
-
-if test $ac_cv_header_stdc = yes; then
-  # ISC 2.0.2 stdlib.h does not declare free, contrary to ANSI.
-  cat >conftest.$ac_ext <<_ACEOF
-#line $LINENO "configure"
-#include "confdefs.h"
-#include <stdlib.h>
-
-_ACEOF
-if (eval "$ac_cpp conftest.$ac_ext") 2>&5 |
-  egrep "free" >/dev/null 2>&1; then
-  :
-else
-  ac_cv_header_stdc=no
-fi
-rm -f conftest*
-
-fi
-
-if test $ac_cv_header_stdc = yes; then
-  # /bin/cc in Irix-4.0.5 gets non-ANSI ctype macros unless using -ansi.
-  if test "$cross_compiling" = yes; then
-  :
-else
-  cat >conftest.$ac_ext <<_ACEOF
-#line $LINENO "configure"
-#include "confdefs.h"
-#include <ctype.h>
-#if ((' ' & 0x0FF) == 0x020)
-# define ISLOWER(c) ('a' <= (c) && (c) <= 'z')
-# define TOUPPER(c) (ISLOWER(c) ? 'A' + ((c) - 'a') : (c))
-#else
-# define ISLOWER(c) (('a' <= (c) && (c) <= 'i') \
-                     || ('j' <= (c) && (c) <= 'r') \
-                     || ('s' <= (c) && (c) <= 'z'))
-# define TOUPPER(c) (ISLOWER(c) ? ((c) | 0x40) : (c))
-#endif
-
-#define XOR(e, f) (((e) && !(f)) || (!(e) && (f)))
-int
-main ()
-{
-  int i;
-  for (i = 0; i < 256; i++)
-    if (XOR (islower (i), ISLOWER (i))
-        || toupper (i) != TOUPPER (i))
-      exit(2);
-  exit (0);
-}
-_ACEOF
-rm -f conftest$ac_exeext
-if { (eval echo "$as_me:$LINENO: \"$ac_link\"") >&5
-  (eval $ac_link) 2>&5
-  ac_status=$?
-  echo "$as_me:$LINENO: \$? = $ac_status" >&5
-  (exit $ac_status); } && { ac_try='./conftest$ac_exeext'
-  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
-  (eval $ac_try) 2>&5
-  ac_status=$?
-  echo "$as_me:$LINENO: \$? = $ac_status" >&5
-  (exit $ac_status); }; }; then
-  :
-else
-  echo "$as_me: program exited with status $ac_status" >&5
-echo "$as_me: failed program was:" >&5
-cat conftest.$ac_ext >&5
-( exit $ac_status )
-ac_cv_header_stdc=no
-fi
-rm -f core core.* *.core conftest$ac_exeext conftest.$ac_objext conftest.$ac_ext
-fi
-fi
-fi
-echo "$as_me:$LINENO: result: $ac_cv_header_stdc" >&5
-echo "${ECHO_T}$ac_cv_header_stdc" >&6
-if test $ac_cv_header_stdc = yes; then
-
-cat >>confdefs.h <<\_ACEOF
-#define STDC_HEADERS 1
-_ACEOF
-
-fi
-
-# On IRIX 5.3, sys/types and inttypes.h are conflicting.
-
-
-
-
-
-
-
-
-
-for ac_header in sys/types.h sys/stat.h stdlib.h string.h memory.h strings.h \
-                  inttypes.h stdint.h unistd.h
-do
-as_ac_Header=`echo "ac_cv_header_$ac_header" | $as_tr_sh`
-echo "$as_me:$LINENO: checking for $ac_header" >&5
-echo $ECHO_N "checking for $ac_header... $ECHO_C" >&6
-if eval "test \"\${$as_ac_Header+set}\" = set"; then
-  echo $ECHO_N "(cached) $ECHO_C" >&6
-else
-  cat >conftest.$ac_ext <<_ACEOF
-#line $LINENO "configure"
-#include "confdefs.h"
-$ac_includes_default
-
-#include <$ac_header>
-_ACEOF
-rm -f conftest.$ac_objext
-if { (eval echo "$as_me:$LINENO: \"$ac_compile\"") >&5
-  (eval $ac_compile) 2>&5
-  ac_status=$?
-  echo "$as_me:$LINENO: \$? = $ac_status" >&5
-  (exit $ac_status); } &&
-         { ac_try='test -s conftest.$ac_objext'
-  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
-  (eval $ac_try) 2>&5
-  ac_status=$?
-  echo "$as_me:$LINENO: \$? = $ac_status" >&5
-  (exit $ac_status); }; }; then
-  eval "$as_ac_Header=yes"
-else
-  echo "$as_me: failed program was:" >&5
-cat conftest.$ac_ext >&5
-eval "$as_ac_Header=no"
-fi
-rm -f conftest.$ac_objext conftest.$ac_ext
-fi
-echo "$as_me:$LINENO: result: `eval echo '${'$as_ac_Header'}'`" >&5
-echo "${ECHO_T}`eval echo '${'$as_ac_Header'}'`" >&6
-if test `eval echo '${'$as_ac_Header'}'` = yes; then
-  cat >>confdefs.h <<_ACEOF
-#define `echo "HAVE_$ac_header" | $as_tr_cpp` 1
-_ACEOF
-
-fi
-
-done
-
-
 
 
 
@@ -17182,6 +17317,8 @@ s,@krb_srvtab@,$krb_srvtab,;t t
 s,@with_pam@,$with_pam,;t t
 s,@with_openssl@,$with_openssl,;t t
 s,@ELF_SYS@,$ELF_SYS,;t t
+s,@THREAD_LIBS@,$THREAD_LIBS,;t t
+s,@THREAD_CFLAGS@,$THREAD_CFLAGS,;t t
 s,@AWK@,$AWK,;t t
 s,@FLEX@,$FLEX,;t t
 s,@FLEXFLAGS@,$FLEXFLAGS,;t t
diff --git a/configure.in b/configure.in
index 2e0a7c8b32..aece9bd6c7 100644
--- a/configure.in
+++ b/configure.in
@@ -1,5 +1,5 @@
 dnl Process this file with autoconf to produce a configure script.
-dnl $Header: /cvsroot/pgsql/configure.in,v 1.253 2003/05/22 16:39:28 tgl Exp $
+dnl $Header: /cvsroot/pgsql/configure.in,v 1.254 2003/05/27 16:36:50 momjian Exp $
 dnl
 dnl Developers, please strive to achieve this order:
 dnl
@@ -506,6 +506,9 @@ PGAC_ARG_BOOL(with, zlib, yes,
               [  --without-zlib          do not use Zlib])
 
 
+#
+# Elf
+#
 
 # Assume system is ELF if it predefines __ELF__ as 1,
 # otherwise believe host_os based default.
@@ -527,7 +530,31 @@ else
 fi])
 AC_SUBST(ELF_SYS)
 
+#
+# Pthreads
+#
 
+AC_CHECK_HEADER(pthread.h,
+	[AC_DEFINE(HAVE_THREADS, 1, [Define to 1 if you have the threads interface.])])
+if test ! -z "$HAVE_THREADS"
+then	
+	case $host_os in
+		# BSD/OS and NetBSD require no special libraries or flags
+		netbsd*|bsdi*) ;;
+		freebsd2*|freebsd3*|freebsd4*) THREAD_CFLAGS="-pthread" ;;
+		freebsd*) THREAD_LIBS="-lc_r" ;;
+		linux*) THREAD_LIBS="-lpthread"
+			THREAD_CFLAGS="-D_REENTRANT" ;;
+	# other operating systems might fail because they have pthread.h but need
+	# special libs we don't know about yet.
+	esac
+fi
+AC_SUBST(THREAD_LIBS)
+AC_SUBST(THREAD_CFLAGS)
+
+#
+# Assignments
+#
 
 CPPFLAGS="$CPPFLAGS $INCLUDES"
 LDFLAGS="$LDFLAGS $LIBDIRS"
diff --git a/src/Makefile.global.in b/src/Makefile.global.in
index 8e75965a9b..b08830bb9f 100644
--- a/src/Makefile.global.in
+++ b/src/Makefile.global.in
@@ -1,5 +1,5 @@
 # -*-makefile-*-
-# $Header: /cvsroot/pgsql/src/Makefile.global.in,v 1.162 2003/05/11 20:50:53 tgl Exp $
+# $Header: /cvsroot/pgsql/src/Makefile.global.in,v 1.163 2003/05/27 16:36:50 momjian Exp $
 
 #------------------------------------------------------------------------------
 # All PostgreSQL makefiles include this file and use the variables it sets,
@@ -152,6 +152,9 @@ TK_LIBS			= @TK_LIBS@
 TK_LIB_SPEC		= @TK_LIB_SPEC@
 TK_XINCLUDES		= @TK_XINCLUDES@
 
+THREAD_CFLAGS		= @THREAD_CFLAGS@
+THREAD_LIBS		= @THREAD_LIBS@
+
 have_docbook	= @have_docbook@
 DOCBOOKSTYLE	= @DOCBOOKSTYLE@
 COLLATEINDEX	= @COLLATEINDEX@
diff --git a/src/include/pg_config.h.in b/src/include/pg_config.h.in
index 129d7396e5..bc6d89ada1 100644
--- a/src/include/pg_config.h.in
+++ b/src/include/pg_config.h.in
@@ -465,6 +465,9 @@
 /* Define to 1 if you have the <termios.h> header file. */
 #undef HAVE_TERMIOS_H
 
+/* Define to 1 if you have the threads interface. */
+#undef HAVE_THREADS
+
 /* Define to 1 if your `struct tm' has `tm_zone'. Deprecated, use
    `HAVE_STRUCT_TM_TM_ZONE' instead. */
 #undef HAVE_TM_ZONE