generating an older version Rails app, how?

Hello,

I have rails-2.0.2 and rails-2.1.0 installed via gem. I want to
generate a rails 2.0.2 app, how do I do that? I tried the following
command and got the following error...

$ ruby /Library/Ruby/Gems/1.8/gems/rails-2.0.2/bin/rails myapp
/Library/Ruby/Gems/1.8/gems/rails-2.0.2/bin/../lib/rails_generator/
options.rb:32:in `default_options': undefined method
`write_inheritable_attribute' for Rails::Generator::Base:Class
(NoMethodError)
        from /Library/Ruby/Gems/1.8/gems/rails-2.0.2/bin/../lib/
rails_generator/base.rb:90
        from /System/Library/Frameworks/Ruby.framework/Versions/1.8/
usr/lib/ruby/1.8/rubygems/custom_require.rb:27:in
`gem_original_require'
        from /System/Library/Frameworks/Ruby.framework/Versions/1.8/
usr/lib/ruby/1.8/rubygems/custom_require.rb:27:in `require'
        from /Library/Ruby/Gems/1.8/gems/rails-2.0.2/bin/../lib/
rails_generator.rb:34
        from /Library/Ruby/Gems/1.8/gems/rails-2.0.2/bin/rails:13:in
`require'
        from /Library/Ruby/Gems/1.8/gems/rails-2.0.2/bin/rails:13

Thanks for the help.

rails _2.0.2_ myapp