memcached::Memcached C++ wrapper doesn't give error codes

[cube45]

The class memcached::Memcached seemed to be great as I am a C++ developer. However, the return types of methods like get or mget are annoying:
Sometimes (for a MEMCACHED_NOTFOUND or a MEMCACHED_DATA_EXISTS for example), the function returns false, but when I get the error codes, it returns MEMCACHED_SUCCESS!

example code:
 std::string key = "key";
 std::vector<char> readData;
 if(!m_memcached->get(key, readData))
 {
  memcached_return_t result = MEMCACHED_SUCCESS;
  m_memcached->error(result);//result can be MEMCACHED_SUCCESS here!
 }