IPC client in asp.net 2.0 Beta 2 gets Access denied error when deployed

[Peter Qian]

Hi All,
I have a simple design where a IPC Client channel sits inside an asp.net
application and talks to a backend custom data provider. It all works great
when I run it under VS 2005's debugging server (the one that comes with VS),
however when I deploy the application using Publish to IIS and run it there,
i got the following error:

Failed To Connect to an IPC Port: Access is denied.
System.Runtime.Remoting.RemotingException: Failed to connect to an IPC
Port: Access is denied.

Any idea what could have caused this?
i have
secure="true" tokenImpersonationLevel="Impersonation"
useDefaultCredentials="true"
on the client channel and
secure="true" impersonate="true"
on the server channel.

Regards

Peter