This was based on Lester Chan's Relative Date plugin. It tries to simplify things a bit. This plugin can:
- Replace the_date() in the post
- Replace get_comment_date() or comment_date() in the comments
Note that if your theme is writing the date in a different form, it won't work. You have to replace its function call to one of the above (in the TwentyTen theme for example, replace twentyten_posted_on() by the_date().
Also important to say that, comment replacement won't work if you are using the default wp comment renderer because it calls get_comment_time() as well. You have to do a customized callback function to use with wp_list_comments( array( 'callback' => 'your_customized_function_here' ) ). (ok, maybe things were not simplified that much :/)
There is a options page (under settings in the Admin) where you can choose which dates you want to replace (posts/comments). Posts date are by default checked.
Portuguese translation included.