Bundler error: undefined method gsub

[darioghilardi]

Running bundler 1.1.3 with the inline_style gem into the Gemfile gives me an undefined method error.

.rvm/gems/ruby-1.9.3-p0/gems/bundler-1.1.3/lib/bundler/runtime.rb:77:in `rescue in rescue in block in require': undefined method `gsub' for nil:NilClass (NoMethodError)
from /Users/ingo/.rvm/gems/ruby-1.9.3-p0/gems/bundler-1.1.3/lib/bundler/runtime.rb:72:in `rescue in block in require'
from /Users/ingo/.rvm/gems/ruby-1.9.3-p0/gems/bundler-1.1.3/lib/bundler/runtime.rb:62:in `block in require'
from /Users/ingo/.rvm/gems/ruby-1.9.3-p0/gems/bundler-1.1.3/lib/bundler/runtime.rb:55:in `each'
from /Users/ingo/.rvm/gems/ruby-1.9.3-p0/gems/bundler-1.1.3/lib/bundler/runtime.rb:55:in `require'
from /Users/ingo/.rvm/gems/ruby-1.9.3-p0/gems/bundler-1.1.3/lib/bundler.rb:119:in `require'
from /Users/ingo/rails_projects/Alduin/config/application.rb:14:in `<top (required)>'
from /Users/ingo/.rvm/gems/ruby-1.9.3-p0/gems/railties-3.2.3/lib/rails/commands.rb:39:in `require'
from /Users/ingo/.rvm/gems/ruby-1.9.3-p0/gems/railties-3.2.3/lib/rails/commands.rb:39:in `<top (required)>'
from script/rails:6:in `require'
from script/rails:6:in `<main>'

A quick debug shows me that the error comes from the require of the inline_style gem.
I tried commenting out the gem from the gemfile and it works. I'm on OSX.