At this point I am not going to modify the provider code, just going to eliminate the login\ logoff, I changed the web .config and went with Windows authentication instead of forms.

<identity impersonate="true"/>
<authentication mode="Windows"/>
<authorization>
      <deny users="?"/>
</authorization>

I have tested it the configuration this morning and so far users gets logged in automatically but when they click the logoff it logs them right back in again. I will let this run for a while in our development environment for a while and see what surfaces before I hide the logoff. Can't see the sence of logoff in an Intranet\AD environment anyway.

Feel free to add your two sence in if you see any problems with this setup.

Thanks

Dan