explained

Javascript Directory 404 Error

---

If your site is hosted on a Debian/Ubuntu server using Apache, you may encounter 404 errors when attempting to use a Javascript directory. You may try to remedy the problem by verifying via ftp or ssh that a javascript directory has actually been created properly and that all permissions are set correctly (e.g. chmod 755, chown), but that is not likely to fix it. This is the consequence of an alias that exists by default which points to "/usr/share/javascript/".

To fix the problem, edit a file named "javascript-common.conf" which is located at "/etc/apache2/conf.d/". Modify the following line:

Alias /javascript /usr/share/javascript/

Change "/javascript" to some other name that doesn't interfere with the directory structure of your site or remove the alias completely if you don't need it.