Eu estou tentando executar o programa, usando código de exemplo do boost :: filesystem no Ubuntu 12.10, mas não quer construir.

#include <iostream>
#include <boost/filesystem.hpp>
using namespace boost::filesystem;
using namespace std;

void fun(const string& dirPath);
int main()
{
    fun("/home");
    return 0;
}

void fun(const string& dirPath)
{
    path p (dirPath); 

    if (exists(p))  
    {
        if (is_regular_file(p))   
            cout << p << " size is " << file_size(p) << '\n';

        else if (is_directory(p))    
            cout << p << "is a directory\n";

        else
            cout << p << "exists, but is neither a regular file nor a directory\n";
    }
    else
        cout << p << "does not exist\n";
}

E código CMake:

project(tttest)
cmake_minimum_required(VERSION 2.8)
aux_source_directory(. SRC_LIST)
add_executable(${PROJECT_NAME} ${SRC_LIST})
FIND_PACKAGE(Boost 1.53 COMPONENTS filesystem system REQUIRED)
include_directories(${Boost_INCLUDE_DIR})
link_directories(${Boost_LIBRARY_DIR})
TARGET_LINK_LIBRARIES(${PROJECT_NAME} ${Boost_LIBRARIES})

Infelizmente gera erros

CMakeFiles/tttest.dir/main.cpp.o: In function `boost::filesystem::exists(boost::filesystem::path const&)':
main.cpp:(.text._ZN5boost10filesystem6existsERKNS0_4pathE[_ZN5boost10filesystem6existsERKNS0_4pathE]+0x19): undefined reference to `boost::filesystem::detail::status(boost::filesystem::path const&, boost::system::error_code*)'
CMakeFiles/tttest.dir/main.cpp.o: In function `boost::filesystem::is_directory(boost::filesystem::path const&)':
main.cpp:(.text._ZN5boost10filesystem12is_directoryERKNS0_4pathE[_ZN5boost10filesystem12is_directoryERKNS0_4pathE]+0x19): undefined reference to `boost::filesystem::detail::status(boost::filesystem::path const&, boost::system::error_code*)'
CMakeFiles/tttest.dir/main.cpp.o: In function `boost::filesystem::is_regular_file(boost::filesystem::path const&)':
main.cpp:(.text._ZN5boost10filesystem15is_regular_fileERKNS0_4pathE[_ZN5boost10filesystem15is_regular_fileERKNS0_4pathE]+0x19): undefined reference to `boost::filesystem::detail::status(boost::filesystem::path const&, boost::system::error_code*)'
CMakeFiles/tttest.dir/main.cpp.o: In function `boost::filesystem::file_size(boost::filesystem::path const&)':
main.cpp:(.text._ZN5boost10filesystem9file_sizeERKNS0_4pathE[_ZN5boost10filesystem9file_sizeERKNS0_4pathE]+0x19): undefined reference to `boost::filesystem::detail::file_size(boost::filesystem::path const&, boost::system::error_code*)'
collect2: error: ld returned 1 exit status

Qual é a razão deste problema e como resolvê-lo?