There is a very good chance its a custom code plugin. You can always email them and ask, its always worth a shot.

You need to learn to use the "view source" of the web site. It tells too much for this site.

In the first few lines I know they are using Wordpress CMS. I know they have a custom theme (the creator of the theme is noted in the footer). I know that it is using xmlrpc.php. And I can figure out what xmlns services it is using. Now the actual services he calls is something he may or may not tell you but it is his bread and butter; however, I bet you can find open source to do the same thing.

i guess this site use custom codes ...