I have two domains on the same server, one of which is a WordPress account. I began setting up the wordpress account before the domain propagated, by using the structure:
www.domainone.com/domaintwo
After the server propagated, I pointed the second domain (the WordPress site) to the correct directory:
www.domaintwo.com
Voila, when I go to www.domain2.com, the front page works, but the links are all now www.domainone.com/domaintwo.
I tried fixing it by dumping the entire MySQL database and doing a search and replace, replacing all www.domainone.com/domaintwo with www.domaintwo.com. After importing this revised database to the server, the first page works, however, all the rest of the site is broken.
I tried changing the .htaccess file, but to no avail. (at least yet).