No.i just have tha same proble m like:I have set up a new forum and am having the login issue that many other people have mentioned where a user logs in successfully, is redirected back to the main page, but then is not actually logged in. This seems to be happening for every user, in IE.
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Uncomment the P3P line in functions.php
Check $cookie_domain = ''
the address is http://fak_kkg.extra.hu maybe it can help you a bit 
