Could not find 'sprockets' (~> 2.2.1) among 166 total gem(s) (Gem::LoadError)

Gemfile

gem 'sprockets',        git: 'http://ift.tt/1Fawop2', branch: '2_2_2_backport2'
gem 'sprockets-rails',  git: 'http://ift.tt/1Fawop4', branch: 'backport'

when we are stating server, we are facing issue

Error:

/home/kannan/.rvm/rubies/ruby-2.1.3/lib/ruby/2.1.0/rubygems/dependency.rb:298:in `to_specs': Could not find 'sprockets' (~> 2.2.1) among 166 total gem(s) (Gem::LoadError)
from /home/kannan/.rvm/rubies/ruby-2.1.3/lib/ruby/2.1.0/rubygems/specification.rb:1295:in `block in activate_dependencies'
from /home/kannan/.rvm/rubies/ruby-2.1.3/lib/ruby/2.1.0/rubygems/specification.rb:1284:in `each'

So that, we are unable to start application. please help us

Ref project http://ift.tt/1s3KFK0

Thanks.