Twitter suggestions returning 404? - ruby-on-rails-3

Question

Running Twitter gem version 1.7.2, OSX Lion, Ruby 1.9.2.
In Rails console.. if you put:
client = Twitter::Client.new(:oauth_token => actual_token_here, :oauth_token_secret => actual_secret_here)
client.suggestions('entertainment')
It retrieves results from Twitter's API. But:
client = Twitter::Client.new
client.suggestions('entertainment')
Returns the same error:
Twitter::NotFound: GET https://api.twitter.com/1/users/suggestions/entertainment.json: 404: Can't find that category
https://dev.twitter.com/docs/api/1/get/users/suggestions/%3Aslug suggests that you don't need to be authenticated to make this API call.
So shouldn't it work without the tokens as well? The strange this is, I've asked someone else to do this on their dev machine and it works fine. I don't know where to proceed from here. How can I track where the problem is coming from?
This is the full trace:
Twitter::NotFound: GET https://api.twitter.com/1/users/suggestions/entertainment.json: 404: Can't find that category
from /Users/Chris/.rvm/gems/ruby-1.9.2-p290/gems/twitter-1.7.2/lib/faraday/response/raise_http_4xx.rb:16:in `on_complete'
from /Users/Chris/.rvm/gems/ruby-1.9.2-p290/gems/faraday-0.7.4/lib/faraday/response.rb:9:in `block in call'
from /Users/Chris/.rvm/gems/ruby-1.9.2-p290/gems/faraday-0.7.4/lib/faraday/response.rb:62:in `on_complete'
from /Users/Chris/.rvm/gems/ruby-1.9.2-p290/gems/faraday-0.7.4/lib/faraday/response.rb:8:in `call'
from /Users/Chris/.rvm/gems/ruby-1.9.2-p290/gems/faraday-0.7.4/lib/faraday/request/url_encoded.rb:14:in `call'
from /Users/Chris/.rvm/gems/ruby-1.9.2-p290/gems/faraday-0.7.4/lib/faraday/request/multipart.rb:13:in `call'
from /Users/Chris/.rvm/gems/ruby-1.9.2-p290/gems/twitter-1.7.2/lib/faraday/request/multipart_with_file.rb:18:in `call'
from /Users/Chris/.rvm/gems/ruby-1.9.2-p290/gems/faraday-0.7.4/lib/faraday/connection.rb:203:in `run_request'
from /Users/Chris/.rvm/gems/ruby-1.9.2-p290/gems/faraday-0.7.4/lib/faraday/connection.rb:85:in `get'
from /Users/Chris/.rvm/gems/ruby-1.9.2-p290/gems/twitter-1.7.2/lib/twitter/request.rb:27:in `request'
from /Users/Chris/.rvm/gems/ruby-1.9.2-p290/gems/twitter-1.7.2/lib/twitter/request.rb:6:in `get'
from /Users/Chris/.rvm/gems/ruby-1.9.2-p290/gems/twitter-1.7.2/lib/twitter/client/user.rb:117:in `suggestions'
from (irb):2
from /Users/Chris/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.1.0/lib/rails/commands/console.rb:45:in `start'
from /Users/Chris/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.1.0/lib/rails/commands/console.rb:8:in `start'
from /Users/Chris/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.1.0/lib/rails/commands.rb:40:in `<top (required)>'
from script/rails:6:in `require'
from script/rails:6:in

Answer 1

Errr. for some reason, I needed to specify the lang param. For example:
client.suggestions("entertainment", :lang => "en")
Works now!