diff --git a/aclocal/ax_boost_base.m4 b/aclocal/ax_boost_base.m4
index c96d1b6..5894d0c 100644
--- a/aclocal/ax_boost_base.m4
+++ b/aclocal/ax_boost_base.m4
@@ -70,11 +70,13 @@
 	if test "$ac_boost_path" != ""; then
 		BOOST_LDFLAGS="-L$ac_boost_path/lib"
 		BOOST_CPPFLAGS="-I$ac_boost_path/include"
+		BOOST_ROOT_PATH="$ac_boost_path"
 	else
 		for ac_boost_path_tmp in /usr /usr/local /opt /opt/local ; do
 			if test -d "$ac_boost_path_tmp/include/boost" && test -r "$ac_boost_path_tmp/include/boost"; then
 				BOOST_LDFLAGS="-L$ac_boost_path_tmp/lib"
 				BOOST_CPPFLAGS="-I$ac_boost_path_tmp/include"
+				BOOST_ROOT_PATH="$ac_boost_path_tmp"
 				break;
 			fi
 		done
@@ -88,6 +90,8 @@
 	LDFLAGS="$LDFLAGS $BOOST_LDFLAGS"
 	export LDFLAGS
 
+	export BOOST_ROOT_PATH
+
 	AC_LANG_PUSH(C++)
      	AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
 	@%:@include <boost/version.hpp>
@@ -141,6 +145,7 @@
 			VERSION_UNDERSCORE=`echo $_version | sed 's/\./_/'`
 			BOOST_CPPFLAGS="-I$best_path/include/boost-$VERSION_UNDERSCORE"
 			BOOST_LDFLAGS="-L$best_path/lib"
+			BOOST_ROOT_PATH="$best_path"
 
 	    		if test "x$BOOST_ROOT" != "x"; then
 				if test -d "$BOOST_ROOT" && test -r "$BOOST_ROOT" && test -d "$BOOST_ROOT/stage/lib" && test -r "$BOOST_ROOT/stage/lib"; then
@@ -152,6 +157,7 @@
 						AC_MSG_NOTICE(We will use a staged boost library from $BOOST_ROOT)
 						BOOST_CPPFLAGS="-I$BOOST_ROOT"
 						BOOST_LDFLAGS="-L$BOOST_ROOT/stage/lib"
+						BOOST_ROOT_PATH="$BOOST_ROOT"
 					fi
 				fi
 	    		fi
@@ -161,6 +167,7 @@
 		export CPPFLAGS
 		LDFLAGS="$LDFLAGS $BOOST_LDFLAGS"
 		export LDFLAGS
+		export BOOST_ROOT_PATH
 
 		AC_LANG_PUSH(C++)
 	     	AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
@@ -189,6 +196,7 @@
 	else
 		AC_SUBST(BOOST_CPPFLAGS)
 		AC_SUBST(BOOST_LDFLAGS)
+		AC_SUBST(BOOST_ROOT_PATH)
 		AC_DEFINE(HAVE_BOOST,,[define if the Boost library is available])
 	fi