track.getCorrection returns exceptions or nil

[masterkain]

69946f0

Lastfm.new(Settings.services.lastfm.api_key, Settings.services.lastfm.secret).track.get_correction('White Stripes', 'One More Cup of Coffee', 'wainekerr')

This uses the same data as in the spec, however it returns nil for me.

If instead we use a mispelt artist or track title, it raises:

Lastfm::ApiError: Supplied artist does not exist
  from /Users/kain/.rvm/gems/ruby-1.9.3-p125/bundler/gems/ruby-lastfm-2242de096b1e/lib/lastfm.rb:96:in `request'
  from /Users/kain/.rvm/gems/ruby-1.9.3-p125/bundler/gems/ruby-lastfm-2242de096b1e/lib/lastfm/method_category/base.rb:54:in `request'
  from /Users/kain/.rvm/gems/ruby-1.9.3-p125/bundler/gems/ruby-lastfm-2242de096b1e/lib/lastfm/method_category/base.rb:29:in `block in __define_method'

[masterkain]

As an added note I don't see the username as required or optional param in here: http://www.lastfm.it/api/show/track.getCorrection