套接字通信故障

>我有一个客户端，它给了我一个非ssl url：port来发送信息（包含xml数据的字符串）到他们的服务器。我曾经使用Putty（在telnet模式下）成功与服务器通信，并收到回复，但是当我使用以下代码时没有进行通信

outputmsg = string.Empty;
                var m_socListener = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.IP);
                IPHostEntry ipAddress = Dns.GetHostEntry("testurlhere");
                var ip = new IPEndPoint(ipAddress.AddressList[0], 10121);
                m_socListener.Connect(ip);
                byte[] tosend = GetBytes(inputmsg);
                byte[] buffer = new byte[1024];
                m_socListener.Send(tosend); // doesnt sends data and returns immediately
                m_socListener.Receive(buffer); // waits forever
                m_socListener.Close();

 static byte[] GetBytes(string str)
        {
            byte[] bytes = new byte[str.Length * sizeof(char)];
            System.Buffer.BlockCopy(str.ToCharArray(), 0, bytes, 0, bytes.Length);
            return bytes;
        }
    static string GetString(byte[] bytes)
    {
        char[] chars = new char[bytes.Length / sizeof(char)];
        System.Buffer.BlockCopy(bytes, 0, chars, 0, bytes.Length);
        return new string(chars);
    }