how to use hash_map with std::string as key type?

[dbtouch]

Dear G++ Users,

I am using g++ (gcc version 4.1.2 20070925 (Red Hat 4.1.2-33)) and I
cannot use hash_map with std::string as key type. Here is the test
program I have:

#include <string>
#include <ext/hash_map>
using namespace __gnu_cxx;

typedef hash_map<std::string, int> MyHashTyp;

int main() {
        MyHashTyp map;
        MyHashTyp::iterator itr;

        itr=map.find(std::string("hello"));
        return 1;
}

The compiler reported error as:

strhashmap.cpp:11:   instantiated from here
/usr/lib/gcc/x86_64-redhat-linux/4.1.2/../../../../include/c++/4.1.2/
ext/hashtable.h:596: error: no match for call to â(const
__gnu_cxx::hash<std::basic_string<char, std::char_traits<char>,
std::allocator<char> > >) (const std::basic_string<char,
std::char_traits<char>, std::allocator<char> >&)â
make: *** [strhashmap.o] Error 1

When I change key type to char, it compiles. Can you help me on this?

Thanks and Happy Chinese New Year!

dbtouch