Need more info... Are you using a CMS or is SMF stand alone? Sounds like you might need to manually go into your settings.conf.php file (or similar file) and change your database settings. You can do this with Dreamweaver or any editor that can handle PHP files... I prefer to use notepad to ensure the file retains it's code integrity. I had a similar problem while trying to bridge SMF with Joomla, so I might be able to help you if you haven't already figured it out.