According to the error message, Safari is trying to reach:
[url]http://bottoms%20up%20burlesque.com/[/url] whatever
Notice the %20 in the URL? Those are spaces. You can't have spaces in the domain name. So the Bulletin Board must have a config file... and in that config file the domain name is specified WITH spaces which is wrong. You might be able to manually access the page by simply trying to go to the page and then removing the %20 's from the URL. Once you do that a few times and you get logged in, then you should be able to use the admin tool to fix the URL (take out the spaces). If you can't use the admin tool at all, then you might need to download the config file with FTP, fix the domain name, and re-upload the config file. If the domain name is saved in a database instead of a config file, then you might need to use a program like PHP-MyAdmin (or use mysql from the command line) to change the domain name in the database.
As you can tell, the solution to your problem largely depends on how the Bulletin Board was built and what tools you have available. In any event, you now know the cause of the error message so now you just need to find a way to fix it.