Topic: rspec installed but unable to run in windows xp

When i run rspec spec/ , it returns the error shown below;

C:/Ruby/lib/ruby/gems/1.8/gems/railties-3.0.0.rc/lib/rails/application.rb:77:in `send': un
defined method `to' for #<SampleApp::Application:0x40acba8> (NoMethodError)
        from C:/Ruby/lib/ruby/gems/1.8/gems/railties-3.0.0.rc/lib/rails/application.rb:77:
in `method_missing'
        from C:/rails_project1/sample_app/config/environments/test.rb:34
        from C:/Ruby/lib/ruby/gems/1.8/gems/railties-3.0.0.rc/lib/rails/application.rb:47:
in `class_eval'
        from C:/Ruby/lib/ruby/gems/1.8/gems/railties-3.0.0.rc/lib/rails/application.rb:47:
in `configure'
        from C:/rails_project1/sample_app/config/environments/test.rb:1
        from C:/Ruby/lib/ruby/gems/1.8/gems/activesupport-3.0.0.rc/lib/active_support/depe
ndencies.rb:219:in `require'
        from C:/Ruby/lib/ruby/gems/1.8/gems/activesupport-3.0.0.rc/lib/active_support/depe
ndencies.rb:219:in `require'
        from C:/Ruby/lib/ruby/gems/1.8/gems/activesupport-3.0.0.rc/lib/active_support/depe
ndencies.rb:205:in `load_dependency'
        from C:/Ruby/lib/ruby/gems/1.8/gems/activesupport-3.0.0.rc/lib/active_support/depe
ndencies.rb:570:in `new_constants_in'
        from C:/Ruby/lib/ruby/gems/1.8/gems/activesupport-3.0.0.rc/lib/active_support/depe
ndencies.rb:205:in `load_dependency'
        from C:/Ruby/lib/ruby/gems/1.8/gems/activesupport-3.0.0.rc/lib/active_support/depe
ndencies.rb:219:in `require'
        from C:/Ruby/lib/ruby/gems/1.8/gems/railties-3.0.0.rc/lib/rails/application/bootst
rap.rb:11
        from C:/Ruby/lib/ruby/gems/1.8/gems/railties-3.0.0.rc/lib/rails/initializable.rb:2
5:in `instance_exec'
        from C:/Ruby/lib/ruby/gems/1.8/gems/railties-3.0.0.rc/lib/rails/initializable.rb:2
5:in `run'
        from C:/Ruby/lib/ruby/gems/1.8/gems/railties-3.0.0.rc/lib/rails/initializable.rb:5
0:in `run_initializers'
        from C:/Ruby/lib/ruby/gems/1.8/gems/railties-3.0.0.rc/lib/rails/initializable.rb:4
9:in `each'
        from C:/Ruby/lib/ruby/gems/1.8/gems/railties-3.0.0.rc/lib/rails/initializable.rb:4
9:in `run_initializers'
        from C:/Ruby/lib/ruby/gems/1.8/gems/railties-3.0.0.rc/lib/rails/application.rb:134
:in `initialize!'
        from C:/Ruby/lib/ruby/gems/1.8/gems/railties-3.0.0.rc/lib/rails/application.rb:77:
in `send'
        from C:/Ruby/lib/ruby/gems/1.8/gems/railties-3.0.0.rc/lib/rails/application.rb:77:
in `method_missing'
        from C:/rails_project1/sample_app/config/environment.rb:5
        from C:/Ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original
_require'
        from C:/Ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `require'
        from C:/rails_project1/sample_app/spec/spec_helper.rb:4
        from C:/Ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original
_require'
        from C:/Ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `require'
        from C:/rails_project1/sample_app/spec/controllers/pages_controller_spec.rb:1
        from C:/Ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original
_require'
        from C:/Ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `require'
        from C:/Ruby/lib/ruby/gems/1.8/gems/rspec-core-2.0.0.beta.18/lib/rspec/core/config
uration.rb:288:in `require_files_to_run'
        from C:/Ruby/lib/ruby/gems/1.8/gems/rspec-core-2.0.0.beta.18/lib/rspec/core/config
uration.rb:288:in `map'
        from C:/Ruby/lib/ruby/gems/1.8/gems/rspec-core-2.0.0.beta.18/lib/rspec/core/config
uration.rb:288:in `require_files_to_run'
        from C:/Ruby/lib/ruby/gems/1.8/gems/rspec-core-2.0.0.beta.18/lib/rspec/core/comman
d_line.rb:18:in `run'
        from C:/Ruby/lib/ruby/gems/1.8/gems/rspec-core-2.0.0.beta.18/lib/rspec/core/runner
.rb:46:in `run_in_process'
        from C:/Ruby/lib/ruby/gems/1.8/gems/rspec-core-2.0.0.beta.18/lib/rspec/core/runner
.rb:37:in `run'
        from C:/Ruby/lib/ruby/gems/1.8/gems/rspec-core-2.0.0.beta.18/lib/rspec/core/runner
.rb:10:in `autorun'
        from C:/Ruby/bin/rspec:19

Thanks for helping