Google-geocode gem not giving an error

Hi,
I doing an integration my rails application with google map. For that I
have installed the "google-geocode (1.2.1)" gem. I have written
following code to get the longitude and latitude of the address.

require 'rubygems'
  require 'google_geocode'
  def index
    gg = GoogleGeocode.new "#{Api_Key}"
   loc = gg.locate('Pune')
   puts loc.inspect
  end

Whenever I running this code I getting following error
"TypeError: can't convert String into Integer
  from
/usr/local/ruby/lib/ruby/gems/1.8/gems/google-geocode-1.2.1/lib/google_geocode.rb:72:in
`[]'
  from
/usr/local/ruby/lib/ruby/gems/1.8/gems/google-geocode-1.2.1/lib/google_geocode.rb:72:in
`check_error'
  from
/usr/local/ruby/lib/ruby/gems/1.8/gems/rc-rest-4.0/lib/rc_rest.rb:128:in
`get'
  from
/usr/local/ruby/lib/ruby/gems/1.8/gems/google-geocode-1.2.1/lib/google_geocode.rb:51:in
`locate'
  from (irb):7"

Can anyone tell me what is the wrong with my code?

Thanks,
Tushar