Membership plugin pop-up box does not detect if user has previously purchased content

I am experiencing a small quirk with the Membership plugin. I have content that I am selling on a page by page basis. Everything is running smoothly regarding the initial purchase transaction and protection of content.

The bug occurs when the user returns to the page at a later date. If they are not already signed in to the site and click the "purchase" button, the purchase/log-in pop-up box displays as expected. However, if this same user (who, once again, has already previously purchased the content) uses the login-in option on the pop-up form, they are THEN prompted to purchase the content a SECOND time.

Now, if the user simply ignores the purchase dialog box, exits the pop-up window, and refreshes the page, they will have access to the protected content as expected. However, I imagine this could be confusing for some of my users and would like to find a fix. Ideally, the pop-up box would automatically detect on sign-in that the user has level access and would return them to the content without prompting for the purchase a second time.

I have a test account and page set up for you to see the problem. Please go to, user name=wpmu, password=test. You have already been granted access to the page, but you will see on sign-in, you are still prompted to pay.