make: Added AC_CONFIG_MACRO_DIR([m4]).
diff --git a/configure.ac b/configure.ac
index c422503..dc9a530 100644
--- a/configure.ac
+++ b/configure.ac
@@ -14,6 +14,7 @@
 AC_INIT([ndn-cpp], [0.2], [ndn-lib@lists.cs.ucla.edu], [ndn-cpp], [https://github.com/named-data/ndn-cpp])
 AM_INIT_AUTOMAKE([1.10 -Wall no-define foreign])
 
+AC_CONFIG_MACRO_DIR([m4])
 AC_CONFIG_SRCDIR([config.h.in])
 # Create config.h without prefixes.
 AC_CONFIG_HEADERS(config.h)
@@ -22,6 +23,8 @@
 AM_MAINTAINER_MODE
 AM_PROG_AR
 AC_PROG_LIBTOOL
+LT_PREREQ([2.2])
+LT_INIT()
 AC_PROG_CXX
 AM_PROG_CC_C_O
 AC_PROG_OBJCXX