I have a server-side asynchronous web method that I built using advice from this article.  http://msdn2.microsoft.com/en-us/library/aa480516.aspx

The web method works great, until I add the soapServerProtocolFactory  configuration tag that adds the WseProtocolFactory to the server side.  It throws a null pointer exception error.  But that error comes from the WSE trying to access the HTTPContext before it has been given back.  I don't know what the real error is.  Has anyone ran into this problem?  Does WSE 3.0 support the server-side asynchronous web method model?  Here is a copy of the error I get.  

Type : System.NullReferenceException, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089 Message : Object reference not set to an instance of an object.
Source : Microsoft.Web.Services3
Help link : 
Data : System.Collections.ListDictionaryInternal
TargetSite : Microsoft.Web.Services3.StateManager GetOrCreateSessionStateFromHttpContext()
Stack Trace :    at Microsoft.Web.Services3.WseProtocol.GetOrCreateSessionStateFromHttpContext()
   at Microsoft.Web.Services3.WseProtocol.GetWriterForMessage(SoapServerMessage message, Int32 bufferSize)
   at System.Web.Services.Protocols.SoapServerProtocol.WriteException(Exception e, Stream outputStream)
   at System.Web.Services.Protocols.WebServiceHandler.WriteException(Exception e)
   at System.Web.Services.Protocols.WebServiceHandler.EndInvoke(IAsyncResult asyncResult)
   at System.Web.Services.Protocols.WebServiceHandler.EndCoreProcessRequest(IAsyncResult asyncResult)
   at System.Web.Services.Protocols.AsyncSessionlessHandler.EndProcessRequest(IAsyncResult asyncResult)
   at System.Web.HttpApplication.CallHandlerExecutionStep.OnAsyncHandlerCompletion(IAsyncResult ar)


Any help?  Notice this is not calling a web method asynchronous , this is a server side asynchronous web method.