Just installed PHPNuke at my site as an upgrade from an old version of just phpbb. Everything has gone smoothly but now I have a nag question. I searched the forums and couldn't locate my problem.

Every time a page in the forums is loaded, no matter what the link is to, I get a nag window popup. Javascript error stating the forums are optimized for Explorer 4+ browsers. I use Mozilla Firebird. How can I remove / disable this warning?

have you checked http://phpbb.com
They might have an answer. I myself have never seen that in the phpBB in Nuke.