AC_HEADER_STDC
AC_HEADER_SYS_WAIT
-test "$db_dir" && CPPFLAGS="$CPPFLAGS -I$db_dir/include"
+test "$db_dir" && CPPFLAGS="$CPPFLAGS -I$db_dir/include" || \
+ ( test -d /usr/include/db3 && CPPFLAGS="$CPPFLAGS -I/usr/include/db3" ) || \
+ ( test -d /usr/local/include/db3 && CPPFLAGS="$CPPFLAGS -I/usr/local/include/db3" )
AC_CHECK_HEADERS(curses.h dl.h fcntl.h limits.h termios.h sys/ioctl.h sys/select.h sys/time.h syslog.h unistd.h utmp.h utmpx.h paths.h db.h db3/db.h)