If you clicked on the calendar archive to the right of the page in the last couple of days you'd notice it didn't allow you to choose "2006" articles.

A quick change to archive.module and all is well. The line in question is this line:

  $years = drupal_map_assoc(range(2000, 2005));

By changing the 2005 to 2006 it again works. However a better solution would include a bit more code that checks for the current year and makes it go through the current year. To save cycles the current year could be specified in a configuration file or stored in the database though each of those has their own issues associated with it.