Facebook fanbox problem

You can use the asynchronous XFBML javascript but you have to register an app and get an appID.

Here is the function I use to add the XFBML to the footer. Note: This will work for the like button also.

add_action('wp_footer', 'c3m_share_this_scripts' );
function c3m_share_this_scripts() {
    echo    '               <script>';
            echo        "               window.fbAsyncInit = function() {;
                        FB.init({appId: 'xxxxxxxxxxxxxxx', status: true, cookie: true,
                                xfbml: true});
                                };";
            echo        "                 (function() {
                                        var e = document.createElement('script'); e.async = true;
                                        e.src = document.location.protocol +
                                          '//connect.facebook.net/en_US/all.js';
                                    document.getElementById('fb-root').appendChild(e);
                                      }());
                                    </script>";
}

Replace the xxxxx’s with your appID

Now to add the like box:

function c3m_facebook_likebox() {
         echo '<fb:like-box href="http://www.facebook.com/your_page_url" width="292" colorscheme="dark" show_faces="true" stream="true" header="true"></fb:like-box>';
}

You can hook the above function into a content hook or just add the c3m_facebook_likebox(); template tag where you want it to show up.