Invisible facebook like button

Hi,

My problem is stupid but can’t fix it… I want to display a like facebook button with counter. I’m using this iframe :

<iframe src="http://www.facebook.com/plugins/like.php?href=<?php echo urlencode(the_permalink($post->ID)); ?>&layout=button_count&show_faces=false&width=90&action=like&font=arial&colorscheme=light&height=65"
    scrolling="no" frameborder="0" style="border:none; height:20px; margin-right:10px; width:90px;" allowTransparency="true"></iframe>

I tried almost all combination for the url : with or whithout urlencode(), $post->ID, “;” or echo but the button still doesn’t appear… But when I echo the permalink, it shows the url. If I try another url (this page for instance) box is shown.

Is it because of linking to localhost ?

Thanks.