Same BUG here, it does not work. One stays logged in. And no normal logout button anywhere. The list does not say that it had been adressed in 1.6.2
Besides there is another problem with the cookies a s I asked in another question, setting one single cookie domain in config as well does not work, may be the same problem somehow.
I changed the settimeout parameter in line 77 of qa-facebook-login.php to 1000, now it "seems" to work. But I think one never should be trapped in the still logged in situation, so a real solution is stil wanted...
setTimeout("window.location=<?php echo qa_js($tourl)?>", 1000);