Directory_iterator - make a copy to rewind?

So, I wrote a small program to try Boost Filesystem. My program will record how many files are in the current path, and then the file names. Here is my program:

#include <iostream>
#include <boost/filesystem.hpp>

using namespace boost::filesystem;

int main(){
    directory_iterator start = directory_iterator(current_path());
    directory_iterator di = start;
    int count;
    for (count = 0; di != directory_iterator(); ++di, ++count);
    std::cout << std::endl << "total number of files: " << count << std::endl;
    di = start;
    for (; di != directory_iterator(); ++di){
        std::cout << *di << std::endl;
    }
    return 0;
}

existing files - program.exe, .ilk and .pdb
However, I get the following result (the entire path is omitted for brevity):

$ program.exe
total files: 3 [..] / program.pdb
The statement failed: m_imp-> m_handle! = 0 && "internal program error", file c: \ program files \ boost \ boost_1_44 \ boost \ filesystem \ v2 \ operations.hpp line 1001

If I create a new directory_iterator, it works fine:

di = start;
// .. becomes ..
di = directory_iterator(current_path());

, directory_iterators, , , .

: startiterator, ?