Character % is not encoded in URLs

[rapenne-s]

When trying to use the app webamp on a directory whose name contains a % character, it fails to load the resources with a http error. The url contains the % character as this, while it should be encoded in %25.

For instance, the directory "100% foobar" would call the url "100%%20foobar" instead of "100%25%20foobar".