If I setup a multitoken option like this:

desc.add_options()
("NumberList", po::value<vector<int> >()->multitoken(), "List of numbers.")

and then call the program with:
./Program --NumberList 1 2 -3 4

it treats the number "-3" as a new flag so it produces an "unknown option" error. Is there a way to handle this negative argument?

Thanks,

David