Add libintl detection for BSD systems.

Patch by Diego Pettenò.
http://bugs.gentoo.org/92586

 #--- configure.in
 #+++ configure.in
 #@@ -72,6 +72,7 @@
 # dnl I18N feature
 # ALL_LINGUAS="cs de el eo es et fr gl hr id it ja ko nl no pl pt_BR ru sl sv"
 # AM_GNU_GETTEXT
 #+AC_CHECK_LIB(intl, libintl_gettext)
 # 
 # dnl DOS file name convention
 # dnl sets HAVE_DOS_FILE_NAMES

--- configure
+++ configure
@@ -7754,6 +8827,80 @@
 
 
 
+echo "$as_me:$LINENO: checking for libintl_gettext in -lintl" >&5
+echo $ECHO_N "checking for libintl_gettext in -lintl... $ECHO_C" >&6
+if test "${ac_cv_lib_intl_libintl_gettext+set}" = set; then
+  echo $ECHO_N "(cached) $ECHO_C" >&6
+else
+  ac_check_lib_save_LIBS=$LIBS
+LIBS="-lintl  $LIBS"
+cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+
+/* Override any gcc2 internal prototype to avoid an error.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+/* We use char because int might match the return type of a gcc2
+   builtin and then its argument prototype would still apply.  */
+char libintl_gettext ();
+int
+main ()
+{
+libintl_gettext ();
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext conftest$ac_exeext
+if { (eval echo "$as_me:$LINENO: \"$ac_link\"") >&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 $ac_status); } &&
+	 { ac_try='test -z "$ac_c_werror_flag"
+			 || test ! -s conftest.err'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; } &&
+	 { ac_try='test -s conftest$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 $ac_status); }; }; then
+  ac_cv_lib_intl_libintl_gettext=yes
+else
+  echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+ac_cv_lib_intl_libintl_gettext=no
+fi
+rm -f conftest.err conftest.$ac_objext \
+      conftest$ac_exeext conftest.$ac_ext
+LIBS=$ac_check_lib_save_LIBS
+fi
+echo "$as_me:$LINENO: result: $ac_cv_lib_intl_libintl_gettext" >&5
+echo "${ECHO_T}$ac_cv_lib_intl_libintl_gettext" >&6
+if test $ac_cv_lib_intl_libintl_gettext = yes; then
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_LIBINTL 1
+_ACEOF
+
+  LIBS="-lintl $LIBS"
+
+fi
+
+
 
   echo "$as_me:$LINENO: checking for dos file convention" >&5
 echo $ECHO_N "checking for dos file convention... $ECHO_C" >&6