FaceBook Drupal integration problem

First of all my approach is in Iframe-approach

Issues,

1. When I logout directly from Facebook interface , application still hold the session & application is in login mode as session-key(db table fb_user_app) doesn't expire(Expiry time in fb_user_app)
so again you login in facebook & try to access & navigate through your application when expiry time over it logout and error throws try to duplicate entry in fb_user_app with UPDATE fb_user_app SET session_key=..,session_key_expires=.. at line 75 of fb_user.module

2. When you post a node from your Drupal application two things happens
a. profile exchange via FB connect
b. Canvas call-back URL & Connect URL being populated through
http://sitename/fb_cb/2/
means deals with an absolute URL in both field & as FaceBook URL construction rule,

If LINK is an absolute URL that is relative to your canvas callback URL (for example, it is the same URL but with added query parameters, or is a subdirectory of the URL), then Facebook just redirects to LINK. Examples of LINK that fall into this category include:
http://apps.facebook.com/foobar/, which redirects to http://www.foobar.com/yourapp/ on your server.

means entire page of application opens instead of within a facebook interface & this is happening first time or when clear my cookie /history of browser
so currently I have put manually the canvas-url to connect URL in facebook apps.... to just by-pass the problem.

Please let me know your view & instruction

Nilanjan