System.Text.ASCIIEncoding encoding = new System.Text.ASCIIEncoding();

            byte[] bytesin = encoding.GetBytes(msgin);
            ProtocolHeader protocolHdr = ProtocolHeader.ReadProtocolHeader(bytesin, 0, msgin.Length);

            MemoryStream hdrin = new MemoryStream(bytesin, Convert.ToInt16(protocolHdr.ProtocolHeaderSize), msgin.Length - Convert.ToInt16(protocolHdr.ProtocolHeaderSize));
            XmlReaderSettings xmlReaderSettings = new XmlReaderSettings();
            xmlReaderSettings.IgnoreWhitespace = true;
            XmlReader msginReader = XmlReader.Create(hdrin, xmlReaderSettings);
            


            while (msginReader.Read())
            {
// ...
            }