Facebook Application shows a page with a "Go to facebook.com" link and Facebook logo: why?

[eluser]Unknown[/eluser]
Hi,

I'm developing a Facebook Application in i-frame using CodeIgniter. I set-up my application, developed it and hosted it.

Now it's available but there is a big problem: when someone arrive on my application he see a page with a link: "Go to Facebook.com" under the Facebook logo. If the user click the link he is redirected to the right page of my Application and all starts working good. But this page is very annoing! Why Facebook shows it? It's a problem with codeigniter+facebook App?

Thanks,

G.