diff --git a/configure b/configure
index e2ed74b270..7d0e639861 100755
--- a/configure
+++ b/configure
@@ -14,7 +14,7 @@
 # OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 # PERFORMANCE OF THIS SOFTWARE.
 #
-# $Id: configure,v 1.461 2009/09/01 17:55:07 jinmei Exp $
+# $Id: configure,v 1.462 2009/09/01 18:41:05 jinmei Exp $
 #
 # Portions Copyright (C) 1996-2001  Nominum, Inc.
 #
@@ -29,7 +29,7 @@
 # WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 # ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
 # OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
-# From configure.in Revision: 1.475 .
+# From configure.in Revision: 1.476 .
 # Guess values for system-dependent variables and create Makefiles.
 # Generated by GNU Autoconf 2.61.
 #
@@ -909,6 +909,9 @@ MKDEPPROG
 IRIX_DNSSEC_WARNINGS_HACK
 purify_path
 PURIFY
+ISC_PLATFORM_USEBACKTRACE
+MKSYMTBL_PROGRAM
+ALWAYS_MAKE_SYMTABLE
 O
 A
 SA
@@ -1650,6 +1653,9 @@ Optional Features:
   --enable-openssl-hash   use OpenSSL for hash functions [default=no]
   --enable-threads	enable multithreading
   --enable-largefile	  64-bit file support
+  --enable-backtrace      log stack backtrace on abort [default=yes]
+  --enable-symtable       use internal symbol table for backtrace
+                          [all|minimal(default)|none]
   --enable-exportlib	build exportable library (GNU make required)
                         [default=no]
   --enable-ipv6           use IPv6 default=autodetect
@@ -3949,7 +3955,7 @@ ia64-*-hpux*)
   ;;
 *-*-irix6*)
   # Find out which ABI we are using.
-  echo '#line 3952 "configure"' > conftest.$ac_ext
+  echo '#line 3958 "configure"' > conftest.$ac_ext
   if { (eval echo "$as_me:$LINENO: \"$ac_compile\"") >&5
   (eval $ac_compile) 2>&5
   ac_status=$?
@@ -6897,11 +6903,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:6900: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:6906: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:6904: \$? = $ac_status" >&5
+   echo "$as_me:6910: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings other than the usual output.
@@ -7187,11 +7193,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:7190: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:7196: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:7194: \$? = $ac_status" >&5
+   echo "$as_me:7200: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings other than the usual output.
@@ -7291,11 +7297,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:7294: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:7300: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>out/conftest.err)
    ac_status=$?
    cat out/conftest.err >&5
-   echo "$as_me:7298: \$? = $ac_status" >&5
+   echo "$as_me:7304: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s out/conftest2.$ac_objext
    then
      # The compiler can only warn and ignore the option if not recognized
@@ -9655,7 +9661,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<EOF
-#line 9658 "configure"
+#line 9664 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -9755,7 +9761,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<EOF
-#line 9758 "configure"
+#line 9764 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -12160,11 +12166,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:12163: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:12169: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:12167: \$? = $ac_status" >&5
+   echo "$as_me:12173: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings other than the usual output.
@@ -12264,11 +12270,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:12267: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:12273: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>out/conftest.err)
    ac_status=$?
    cat out/conftest.err >&5
-   echo "$as_me:12271: \$? = $ac_status" >&5
+   echo "$as_me:12277: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s out/conftest2.$ac_objext
    then
      # The compiler can only warn and ignore the option if not recognized
@@ -13847,11 +13853,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:13850: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:13856: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:13854: \$? = $ac_status" >&5
+   echo "$as_me:13860: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings other than the usual output.
@@ -13951,11 +13957,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:13954: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:13960: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>out/conftest.err)
    ac_status=$?
    cat out/conftest.err >&5
-   echo "$as_me:13958: \$? = $ac_status" >&5
+   echo "$as_me:13964: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s out/conftest2.$ac_objext
    then
      # The compiler can only warn and ignore the option if not recognized
@@ -16162,11 +16168,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:16165: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:16171: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:16169: \$? = $ac_status" >&5
+   echo "$as_me:16175: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings other than the usual output.
@@ -16452,11 +16458,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:16455: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:16461: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:16459: \$? = $ac_status" >&5
+   echo "$as_me:16465: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings other than the usual output.
@@ -16556,11 +16562,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:16559: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:16565: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>out/conftest.err)
    ac_status=$?
    cat out/conftest.err >&5
-   echo "$as_me:16563: \$? = $ac_status" >&5
+   echo "$as_me:16569: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s out/conftest2.$ac_objext
    then
      # The compiler can only warn and ignore the option if not recognized
@@ -19490,6 +19496,8 @@ fi
 
 #
 # Perl is optional; it is used only by some of the system test scripts.
+# Note: the backtrace feature (see below) uses perl to build the symbol table,
+# but it still compiles without perl, in which case an empty table will be used.
 #
 for ac_prog in perl5 perl
 do
@@ -25914,6 +25922,108 @@ case $use_libtool in
 		;;
 esac
 
+#
+# enable/disable dumping stack backtrace.  Also check if the system supports
+# glibc-compatible backtrace() function.
+#
+# Check whether --enable-backtrace was given.
+if test "${enable_backtrace+set}" = set; then
+  enableval=$enable_backtrace; want_backtrace="$enableval"
+else
+  want_backtrace="yes"
+fi
+
+case $want_backtrace in
+yes)
+	ISC_PLATFORM_USEBACKTRACE="#define ISC_PLATFORM_USEBACKTRACE 1"
+	cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+#include <execinfo.h>
+int
+main ()
+{
+return (backtrace((void **)0, 0));
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext conftest$ac_exeext
+if { (ac_try="$ac_link"
+case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval "echo \"\$as_me:$LINENO: $ac_try_echo\"") >&5
+  (eval "$ac_link") 2>conftest.er1
+  ac_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } && {
+	 test -z "$ac_c_werror_flag" ||
+	 test ! -s conftest.err
+       } && test -s conftest$ac_exeext &&
+       $as_test_x conftest$ac_exeext; then
+
+cat >>confdefs.h <<\_ACEOF
+#define HAVE_LIBCTRACE
+_ACEOF
+
+else
+  echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+
+fi
+
+rm -f core conftest.err conftest.$ac_objext conftest_ipa8_conftest.oo \
+      conftest$ac_exeext conftest.$ac_ext
+	;;
+*)
+	ISC_PLATFORM_USEBACKTRACE="#undef ISC_PLATFORM_USEBACKTRACE"
+	;;
+esac
+
+
+# Check whether --enable-symtable was given.
+if test "${enable_symtable+set}" = set; then
+  enableval=$enable_symtable; want_symtable="$enableval"
+else
+  want_symtable="minimal"
+fi
+
+case $want_symtable in
+yes|all|minimal)
+
+	if test "$PERL" == ""
+	then
+		{ { echo "$as_me:$LINENO: error: Internal symbol table requires perl but no perl is found.
+Install perl or explicitly disable the feature by --disable-symtable." >&5
+echo "$as_me: error: Internal symbol table requires perl but no perl is found.
+Install perl or explicitly disable the feature by --disable-symtable." >&2;}
+   { (exit 1); exit 1; }; }
+	fi
+	if test "$use_libtool" = "yes"; then
+		{ echo "$as_me:$LINENO: WARNING: Internal symbol table does not work with libtool.  Disabling symtbol table." >&5
+echo "$as_me: WARNING: Internal symbol table does not work with libtool.  Disabling symtbol table." >&2;}
+	else
+		MKSYMTBL_PROGRAM="$PERL"
+		if test $want_symtable = all; then
+			ALWAYS_MAKE_SYMTABLE="yes"
+		fi
+	fi
+	;;
+*)
+	;;
+esac
+
+
+
 #
 # File name extension for static archive files, for those few places
 # where they are treated differently from dynamic ones.
@@ -34053,6 +34163,9 @@ MKDEPPROG!$MKDEPPROG$ac_delim
 IRIX_DNSSEC_WARNINGS_HACK!$IRIX_DNSSEC_WARNINGS_HACK$ac_delim
 purify_path!$purify_path$ac_delim
 PURIFY!$PURIFY$ac_delim
+ISC_PLATFORM_USEBACKTRACE!$ISC_PLATFORM_USEBACKTRACE$ac_delim
+MKSYMTBL_PROGRAM!$MKSYMTBL_PROGRAM$ac_delim
+ALWAYS_MAKE_SYMTABLE!$ALWAYS_MAKE_SYMTABLE$ac_delim
 O!$O$ac_delim
 A!$A$ac_delim
 SA!$SA$ac_delim
@@ -34103,9 +34216,6 @@ ISC_LWRES_GETNETBYADDRINADDR!$ISC_LWRES_GETNETBYADDRINADDR$ac_delim
 ISC_LWRES_SETNETENTINT!$ISC_LWRES_SETNETENTINT$ac_delim
 ISC_LWRES_ENDNETENTINT!$ISC_LWRES_ENDNETENTINT$ac_delim
 ISC_LWRES_GETHOSTBYADDRVOID!$ISC_LWRES_GETHOSTBYADDRVOID$ac_delim
-ISC_LWRES_NEEDHERRNO!$ISC_LWRES_NEEDHERRNO$ac_delim
-ISC_LWRES_GETIPNODEPROTO!$ISC_LWRES_GETIPNODEPROTO$ac_delim
-ISC_LWRES_GETADDRINFOPROTO!$ISC_LWRES_GETADDRINFOPROTO$ac_delim
 _ACEOF
 
   if test `sed -n "s/.*$ac_delim\$/X/p" conf$$subs.sed | grep -c X` = 97; then
@@ -34147,6 +34257,9 @@ _ACEOF
 ac_delim='%!_!# '
 for ac_last_try in false false false false false :; do
   cat >conf$$subs.sed <<_ACEOF
+ISC_LWRES_NEEDHERRNO!$ISC_LWRES_NEEDHERRNO$ac_delim
+ISC_LWRES_GETIPNODEPROTO!$ISC_LWRES_GETIPNODEPROTO$ac_delim
+ISC_LWRES_GETADDRINFOPROTO!$ISC_LWRES_GETADDRINFOPROTO$ac_delim
 ISC_LWRES_GETNAMEINFOPROTO!$ISC_LWRES_GETNAMEINFOPROTO$ac_delim
 ISC_IRS_GETNAMEINFOSOCKLEN!$ISC_IRS_GETNAMEINFOSOCKLEN$ac_delim
 ISC_PLATFORM_NEEDSTRSEP!$ISC_PLATFORM_NEEDSTRSEP$ac_delim
@@ -34226,7 +34339,7 @@ LIBOBJS!$LIBOBJS$ac_delim
 LTLIBOBJS!$LTLIBOBJS$ac_delim
 _ACEOF
 
-  if test `sed -n "s/.*$ac_delim\$/X/p" conf$$subs.sed | grep -c X` = 77; then
+  if test `sed -n "s/.*$ac_delim\$/X/p" conf$$subs.sed | grep -c X` = 80; then
     break
   elif $ac_last_try; then
     { { echo "$as_me:$LINENO: error: could not make $CONFIG_STATUS" >&5