URI route doesn't work

[eluser]Unknown[/eluser]
My routes file has the default_controller equals to login class, for example.
For the specified class on the default_controler, if the
URI contains no data, code igniter redirect to the implemented page. But if URI contains data, it doesn't redirect.

Example:www.teste.com.br --> redirects to the login page.
www.teste.com.br/login --> doesn't work.

Any idea of what is happening?