$bundle install
/home/anil/.rvm/gems/ruby-1.9.2-head@rails3/gems/bundler-1.0.0.beta.8/lib/bundler/dsl.rb:214:in `block in _normalize_options': `mri_18` is not a valid platform. The available options are: [:ruby_18, :ruby_19, :ruby, :jruby, :mswin] (Bundler::DslError)
	from /home/anil/.rvm/gems/ruby-1.9.2-head@rails3/gems/bundler-1.0.0.beta.8/lib/bundler/dsl.rb:212:in `each'
	from /home/anil/.rvm/gems/ruby-1.9.2-head@rails3/gems/bundler-1.0.0.beta.8/lib/bundler/dsl.rb:212:in `_normalize_options'
	from /home/anil/.rvm/gems/ruby-1.9.2-head@rails3/gems/bundler-1.0.0.beta.8/lib/bundler/dsl.rb:60:in `gem'
	from /home/anil/Dropbox/Code/ubuntu_code/rails/rails/Gemfile:23:in `block in build'
	from /home/anil/.rvm/gems/ruby-1.9.2-head@rails3/gems/bundler-1.0.0.beta.8/lib/bundler/dsl.rb:133:in `platforms'
	from /home/anil/Dropbox/Code/ubuntu_code/rails/rails/Gemfile:22:in `build'
	from /home/anil/.rvm/gems/ruby-1.9.2-head@rails3/gems/bundler-1.0.0.beta.8/lib/bundler/definition.rb:17:in `instance_eval'
	from /home/anil/.rvm/gems/ruby-1.9.2-head@rails3/gems/bundler-1.0.0.beta.8/lib/bundler/definition.rb:17:in `build'
	from /home/anil/.rvm/gems/ruby-1.9.2-head@rails3/gems/bundler-1.0.0.beta.8/lib/bundler.rb:126:in `definition'
	from /home/anil/.rvm/gems/ruby-1.9.2-head@rails3/gems/bundler-1.0.0.beta.8/lib/bundler/cli.rb:115:in `install'
	from /home/anil/.rvm/gems/ruby-1.9.2-head@rails3/gems/bundler-1.0.0.beta.8/lib/bundler/vendor/thor/task.rb:22:in `run'
	from /home/anil/.rvm/gems/ruby-1.9.2-head@rails3/gems/bundler-1.0.0.beta.8/lib/bundler/vendor/thor/invocation.rb:109:in `block in invoke'
	from /home/anil/.rvm/gems/ruby-1.9.2-head@rails3/gems/bundler-1.0.0.beta.8/lib/bundler/vendor/thor/invocation.rb:116:in `call'
	from /home/anil/.rvm/gems/ruby-1.9.2-head@rails3/gems/bundler-1.0.0.beta.8/lib/bundler/vendor/thor/invocation.rb:116:in `invoke'
	from /home/anil/.rvm/gems/ruby-1.9.2-head@rails3/gems/bundler-1.0.0.beta.8/lib/bundler/vendor/thor.rb:161:in `block in start'
	from /home/anil/.rvm/gems/ruby-1.9.2-head@rails3/gems/bundler-1.0.0.beta.8/lib/bundler/vendor/thor/base.rb:379:in `start'
	from /home/anil/.rvm/gems/ruby-1.9.2-head@rails3/gems/bundler-1.0.0.beta.8/lib/bundler/vendor/thor.rb:140:in `start'
	from /home/anil/.rvm/gems/ruby-1.9.2-head@rails3/gems/bundler-1.0.0.rc.1/bin/bundle:13:in `<top (required)>'
	from /home/anil/.rvm/gems/ruby-1.9.2-head@rails3/bin/bundle:19:in `load'
	from /home/anil/.rvm/gems/ruby-1.9.2-head@rails3/bin/bundle:19:in `<main>'