How do I log in to my Seam application using a servlet?

[zzztimbo]

How do I log in to my Seam application without having to be confronted with a login page (without using a JSF page to log in).

My current approach is to pass the username and password to a servlet in Seam. This is currently working. Then I would like to be able to use

Identity.instance().setUsername(userid);
Identity.instance().setPassword(password);

This part is not working. I receive an exception:

java.lang.IllegalStateException: No active session context

I have also asked about this problem in this post:
http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4069335#4069335

Should I take a different approach? Any suggestions are welcomed.

[zzztimbo]

What does the following mean?

The context filter expects to find the conversation id of any conversation context in a request parameter named conversationId. You are responsible for ensuring that it gets sent in the request.

You are also responsible for ensuring propagation of any new conversation id back to the client. Seam exposes the conversation id as a property of the built in component conversation.