Error when running rake task for spree

gistfile1.txt

$ rake paperclip:refresh:thumbnails CLASS=Spree::Image
rake aborted!
795: unexpected token at '{:mini=>"244x173>", :small=>"236x236>", :roteiro=>"312x391>", :big=>"472x472>", :product=>"645x645>"}'
/home/cassio/.rvm/gems/ruby-2.0.0-p195@marazul/gems/json-1.8.0/lib/json/common.rb:155:in `parse'
/home/cassio/.rvm/gems/ruby-2.0.0-p195@marazul/gems/json-1.8.0/lib/json/common.rb:155:in `parse'
/home/cassio/.rvm/gems/ruby-2.0.0-p195@marazul/gems/multi_json-1.8.0/lib/multi_json/adapters/json_common.rb:16:in `load'
/home/cassio/.rvm/gems/ruby-2.0.0-p195@marazul/gems/multi_json-1.8.0/lib/multi_json/adapter.rb:20:in `load'
/home/cassio/.rvm/gems/ruby-2.0.0-p195@marazul/gems/multi_json-1.8.0/lib/multi_json.rb:120:in `load'
/home/cassio/.rvm/gems/ruby-2.0.0-p195@marazul/gems/activesupport-4.0.0/lib/active_support/json/decoding.rb:17:in `decode'
/home/cassio/.rvm/gems/ruby-2.0.0-p195@marazul/gems/spree_core-2.1.1/app/models/spree/image.rb:20:in `<class:Image>'
/home/cassio/.rvm/gems/ruby-2.0.0-p195@marazul/gems/spree_core-2.1.1/app/models/spree/image.rb:2:in `<module:Spree>'
/home/cassio/.rvm/gems/ruby-2.0.0-p195@marazul/gems/spree_core-2.1.1/app/models/spree/image.rb:1:in `<top (required)>'
/home/cassio/.rvm/gems/ruby-2.0.0-p195@marazul/gems/activesupport-4.0.0/lib/active_support/dependencies.rb:423:in `load'
/home/cassio/.rvm/gems/ruby-2.0.0-p195@marazul/gems/activesupport-4.0.0/lib/active_support/dependencies.rb:423:in `block in load_file'
/home/cassio/.rvm/gems/ruby-2.0.0-p195@marazul/gems/activesupport-4.0.0/lib/active_support/dependencies.rb:615:in `new_constants_in'
/home/cassio/.rvm/gems/ruby-2.0.0-p195@marazul/gems/activesupport-4.0.0/lib/active_support/dependencies.rb:422:in `load_file'
/home/cassio/.rvm/gems/ruby-2.0.0-p195@marazul/gems/activesupport-4.0.0/lib/active_support/dependencies.rb:323:in `require_or_load'
/home/cassio/.rvm/gems/ruby-2.0.0-p195@marazul/gems/activesupport-4.0.0/lib/active_support/dependencies.rb:462:in `load_missing_constant'
/home/cassio/.rvm/gems/ruby-2.0.0-p195@marazul/gems/activesupport-4.0.0/lib/active_support/dependencies.rb:183:in `const_missing'
/home/cassio/.rvm/gems/ruby-2.0.0-p195@marazul/gems/paperclip-3.4.2/lib/paperclip/helpers.rb:47:in `block in class_for'
/home/cassio/.rvm/gems/ruby-2.0.0-p195@marazul/gems/paperclip-3.4.2/lib/paperclip/helpers.rb:43:in `each'
/home/cassio/.rvm/gems/ruby-2.0.0-p195@marazul/gems/paperclip-3.4.2/lib/paperclip/helpers.rb:43:in `inject'
/home/cassio/.rvm/gems/ruby-2.0.0-p195@marazul/gems/paperclip-3.4.2/lib/paperclip/helpers.rb:43:in `class_for'
/home/cassio/.rvm/gems/ruby-2.0.0-p195@marazul/gems/paperclip-3.4.2/lib/tasks/paperclip.rake:10:in `obtain_attachments'
/home/cassio/.rvm/gems/ruby-2.0.0-p195@marazul/gems/paperclip-3.4.2/lib/tasks/paperclip.rake:30:in `block (3 levels) in <top (required)>'
Tasks: TOP => paperclip:refresh:thumbnails
(See full trace by running task with --trace)