undefined method 'inline' for ImageScience:Class (NoMethodError)

I am migrating a Rails 2.1.2 application to Rails 2.3.11

To make my life easier i used bundler but I get the following error when starting my server:

/Library/Ruby/Gems/1.8/gems/image_science-1.2.1/lib/image_science.rb:90: undefined method `inline' for ImageScience:Class (NoMethodError)
        from /Library/Ruby/Gems/1.8/gems/bundler-1.0.7/lib/bundler/runtime.rb:64:in `require'
        from /Library/Ruby/Gems/1.8/gems/bundler-1.0.7/lib/bundler/runtime.rb:64:in `require'
        from /Library/Ruby/Gems/1.8/gems/bundler-1.0.7/lib/bundler/runtime.rb:62:in `each'
        from /Library/Ruby/Gems/1.8/gems/bundler-1.0.7/lib/bundler/runtime.rb:62:in `require'
        from /Library/Ruby/Gems/1.8/gems/bundler-1.0.7/lib/bundler/runtime.rb:51:in `each'
        from /Library/Ruby/Gems开发者_开发问答/1.8/gems/bundler-1.0.7/lib/bundler/runtime.rb:51:in `require'
        from /Library/Ruby/Gems/1.8/gems/bundler-1.0.7/lib/bundler.rb:112:in `require'
        from ./script/../config/boot.rb:113:in `load_gems'
        from /Library/Ruby/Gems/1.8/gems/rails-2.3.11/lib/initializer.rb:164:in `process'
        from /Library/Ruby/Gems/1.8/gems/rails-2.3.11/lib/initializer.rb:113:in `send'
        from /Library/Ruby/Gems/1.8/gems/rails-2.3.11/lib/initializer.rb:113:in `run'
        from /Users/michaelkoper/code/beruby_git/config/environment.rb:18
        from /Library/Ruby/Gems/1.8/gems/activesupport-2.3.11/lib/active_support/dependencies.rb:182:in `require'
        from /Library/Ruby/Gems/1.8/gems/activesupport-2.3.11/lib/active_support/dependencies.rb:182:in `require'
        from /Library/Ruby/Gems/1.8/gems/activesupport-2.3.11/lib/active_support/dependencies.rb:547:in `new_constants_in'
        from /Library/Ruby/Gems/1.8/gems/activesupport-2.3.11/lib/active_support/dependencies.rb:182:in `require'
        from /Library/Ruby/Gems/1.8/gems/rails-2.3.11/lib/commands/server.rb:84
        from script/server:3:in `require'
        from script/server:3

It is kind of strange because i got it working without bundler. I think i am missing a gem dependency.

Gemfile:

    gem 'mperham-deadlock_retry', :require => 'deadlock_retry'
    gem 'hoptoad_notifier', '2.4.2'
    gem 'will_paginate', '~> 2.3.15'
    gem "activemerchant", :require => "active_merchant"
    gem "newrelic_rpm"
    gem 'calendar_date_select'
    gem 'ckeditor', '3.4.3'     gem 'automatic_foreign_key'
    gem 'chronic'
    gem 'mechanize'
    gem 'rexml-expansion-fix'
    gem 'image_science', '1.2.1'
    gem 'inline', '0.1.0'

bundle install:

    Using rake (0.8.7) 
    Using activesupport (2.3.11) 
    Using rack (1.1.2) 
    Using actionpack (2.3.11) 
    Using actionmailer (2.3.11) 
    Using builder (3.0.0) 
    Using braintree (2.10.0) 
    Using activemerchant (1.14.0) 
    Using activerecord (2.3.11) 
    Using activeresource (2.3.11) 
    Using redhillonrails_core (1.1.3) 
    Using automatic_foreign_key (1.2.0) 
    Using calendar_date_select (1.16.2) 
    Using cgi_multipart_eof_fix (2.5.0) 
    Using hoe (2.8.0) 
    Using chronic (0.2.3) 
    Using mime-types (1.16) 
    Using ckeditor (3.4.3) 
    Using columnize (0.3.2) 
    Using daemons (1.0.10) 
    Using fastthread (1.0.7) 
    Using gem_plugin (0.2.3) 
    Using highline (1.6.1) 
    Using hoptoad_notifier (2.4.2) 
    Using image_science (1.2.1) 
    Using inline (0.1.0) 
    Using linecache (0.43) 
    Using nokogiri (1.4.4) 
    Using mechanize (0.9.3) 
    Using mongrel (1.1.5) 
    Using mperham-deadlock_retry (1.0.0) 
    Using mysql (2.8.1) 
    Using newrelic_rpm (2.14.1) 
    Using rails (2.3.11) 
    Using rexml-expansion-fix (1.0.1) 
    Using ruby-debug-base (0.10.4) 
    Using ruby-debug (0.10.4) 
    Using will_paginate (2.3.15) 
    Using bundler (1.0.7) 

Actually, it looks like you probably want this answer: ImageScience breaks on update to Rails 3