The problem is when I upload the files of the project to my website (hosted at LunarPages, which supports servlets and jsp's), I get a 404 error (page not found). I kept the directory structure exactly the way I had it in my hard-drive:
But it looks like the site is set up as a web server (ie serving static content) not an application server (serving dynamic content). A quick way to check would be to request WEB-INF/web.xml and see if you get anything back. A Web server will return it, an application server protects this directory and will not.