The post you linked to is only for user's that Like your Facebook Page, not a Like click for a page from your site. JFBConnect does have a "Reveal Page" feature, which requires the user to Like your Facebook Page before seeing other content within the Facebook Page area.
We have no such feature for requiring a user to Like content or your Facebook Page in order to see your content on your site. While it may be technically possible, it would violate Facebook's terms of service which strictly prohibit incentives for clicking the Like button. They want users to only click the Like button when they want too on their own, not because of rewards for doing so. Violations of their policies can get your application banned, your website's use of any of the Facebook social tools (Like, Comment, etc) revoked, or other types of repercussions.
Hope that helps explain,
Alex
Feature Request: FB Like to access content
