[Plugin: Simple Facebook Connect] Using both STC and SFC – SFC button will not appear

Hello their,

I’m using both plugins STC and SFC – SFC button will not appear.
I added the follwing code to my comment-template:

<div id="comment-user-details"> <?php do_action('alt_comment_login'); ?>
        <p><input type="text" name="author" id="author" value="<?php echo $comment_author; ?>" size="22" />
        <label for="author">Name<?php if ($req) _e(' *'); ?></label></p>

        <p><input type="text" name="email" id="email" value="<?php echo $comment_author_email; ?>" size="22" />
        <label for="email">E-mail <?php if ($req) _e(' *'); ?></label></p>

        <p><input type="text" name="url" id="url" value="<?php echo $comment_author_url; ?>" size="22" />
        <label for="url">Website</label></p>

	</div>

I can see the text “Connect with Facebook” on the page but there is no button.

Instead of this the twitter-login works pretty well.

What’s wrong?
Thank you!