Deserialising ebMS 3.0 Headers

The class below is my first attempt at being able to read the ebMS 3.0 headers in C#.  It deserialises the xml into the objects I have created from the xsd files (see previous post).  So you'll need the auto-generated C# classes to use this code.  I'll post an example useage in another blog.  So far I have tested it on all the examples extracted from the ebMS core spec and it seems to load the data OK.

using System;
using System.Collections.Generic;
 
using System.IO;
using System.Xml;
using System.Xml.Serialization;
using System.ServiceModel.Channels;
 
namespace ebMS3.Soap
{
    public class MessageDecoder
    {
        private string _xmlnamespace = null;
        public Message Message { get; private set; } 
 
        public MessageDecoder(Stream stream)
        {
            _xmlnamespace = GetXmlNamespace(typeof(Messaging));
            Message = GetMessage(stream);  
        }
 
        public MessageDecoder(byte[] rawbytes)
        {
            _xmlnamespace = GetXmlNamespace(typeof(Messaging));
            MemoryStream ms = new MemoryStream(rawbytes); 
            Message = GetMessage(ms);
        }
 
        private string GetXmlNamespace(Type t)
        {
            XmlTypeAttribute[] attrs = (XmlTypeAttribute[])
                t.GetCustomAttributes(typeof(XmlTypeAttribute), true);
            if (attrs != null && attrs.Length > 0)
                return attrs[0].Namespace;
            else
                return "";
        }
 
        public UserMessage[] GetHeaderUserMessages()
        {
            return GetHeaderMessages<UserMessage>();
        }
 
        public SignalMessage[] GetHeaderSignalMessages()
        {
            return GetHeaderMessages<SignalMessage>();
        }
 
        private T[] GetHeaderMessages<T>() where T : class
        {
            if (Message == null || Message.Headers == null) return default(T[]);
            List<T> retval = new List<T>();
            XmlSerializer xs = new XmlSerializer(typeof(T), _xmlnamespace);
 
            XmlNode[] hdrs =
                Message.Headers.GetHeader<XmlNode[]>("Messaging", _xmlnamespace);
            foreach (XmlNode xn in hdrs)
            {
                if (xn.Name.EndsWith(typeof(T).Name))
                {
                    T um = xs.Deserialize(new XmlNodeReader(xn)) as T;
                    if (um != null) retval.Add(um);
                }
            }
            return retval.ToArray();
        }
 
        private Message GetMessage(Stream stream)
        {
            MessageVersion soap11 = MessageVersion.Soap11WSAddressingAugust2004;
            XmlReader xreader = XmlReader.Create(stream);
            return Message.CreateMessage(xreader, 5120, soap11); // 5Kb in headers
        }
    }
}