Verification in iRule that SSO Configuration HTTP BASIC was done?

I am trying to implement multiple form fills for one application. An application is deployed at http://site.com/ne There is a web form based login page there at that uri as well as being challenged by a weblogic system prompt. Ive set up a HTTP BASIC SSO Configuration and attached it to the Access Policy which takes care of the weblogic system prompt. I have a forms based SSO Configuration that Im calling from the iRule to handle the web form based login page, but when called from the iRule it overruns the HTTP BASIC SSO config, and I still get the weblogic prompt then. I cant conditionally call the Forms based SSO config based on URI because the weblogic authentication is configured to challenge there as well.. I need a way to check that the HTTP BASIC SSO has been successfully done from within the iRule. I thought I should be able to check the header for the Authorization field, but it seems that when you use an HTTP BASIC SSO configuration, the Authorization field is not then included in the header after authentication (Im checking the header from the ACCESS_ACL_ALLOWED event). Is there a way to know then from within the iRule that the HTTP BASIC SSO config has been done?