http://r.php/ facebook sign up - not working

Do anyone know about this? javascript php facebook facebook-javascript-sdk
It has become an issue on many individuals...! But we are working on it...!

http://r.php/ facebook sign up - not working

I pasted the "Like" code snippet of facebook into my page. if i am logged in in facebook, everything is okay. but if i am not registered in facebook(if i open in different browser), and if i click the sign-up button, then i am getting a page saying: page not found and url is becoming http://r.php/

why is this? this is code of facebook:

<script>(function(d, s, id) {
    var js, fjs = d.getElementsByTagName(s)[0];
        if (d.getElementById(id)) return;
            js = d.createElement(s); js.id = id;
            js.src = "//connect.facebook.net/en_US/all.js#xfbml=1";
            fjs.parentNode.insertBefore(js, fjs);
    }(document, 'script', 'facebook-jssdk'));
</script>

html

<div class="fb-like" data-href="http://www.places4two.de/" data-width="450" data-show-faces="true" data-send="true"> </div>

javascript php facebook facebook-javascript-sdk