How to throw standard exceptions ?

Hello

Almost every program I write starts by checking the number
of arguments and throws an exception if the syntax is not
right. And every time I get the same error: the exception
is not caught with its type, but with the last catch (...)
handler !

Here's an almost minimal example.
Can anyone please tell me what is wrong with my code ?

#include <stdexcept>
#include <iostream>
#include <cstdio>

using namespace std;

int main(int argc, const char *argv[])
     try
{
     if (argc != 3)
    throw
        new
        runtime_error
            (
            "Processes a Filemon log file and re-creates "
                "the directories and files listed\n"
            "into the given path.\n"
            "Syntax:\n"
            "\tclassify LogFile.LOG \\root_path\n"
            "\n"
            );
     else
     {
    // Some processing
    // ...

    return EXIT_SUCCESS;
     }
}
catch (const runtime_error &e)
{
     cerr << "Error:\n";
     cerr << e.what();
     cerr << endl;

     return EXIT_FAILURE;
}
catch(const exception &e)
{
     cerr << "Error:\n";
     cerr << e.what();
     cerr << endl;

     return EXIT_FAILURE;
}
catch (...)
{
     cerr << "General error.\n";

     return EXIT_FAILURE;
}

When I compile and run my program I get:

adrian@darkstar: g++ -o command command.cc
adrian@darkstar: ./command
General failure.

I have tried with Slackware Linux 2.6.14 gcc 4.2.4
and mingw on Win32, gcc 3 ...

Thank you,
Timothy Madden