--format "documentation" is not a valid class name (RuntimeError)

[rajars2576]

while I am running the tasks using

Spec::Rake::SpecTask.new('SampleTest') do |t|
desc "A TestSuite on InternetExplorer on Windows OS X"
t.libs << "test"
t.spec_files = FileList['Init_loader.rb','SampleTest.rb']

t.spec_files = FileList['Init_loader.rb','../Doctor/FridayExecution/*/.rb']

t.spec_files = FileList['Init_loader.rb','TuesdayExecution/40_TuesdayExecution_Lawyer_MD.rb']

t.spec_opts << '--color'
t.spec_opts << "--require 'rubygems,selenium/rspec/reporting/selenium_test_report_formatter'"
t.spec_opts << "--format=Selenium::RSpec::SeleniumTestReportFormatter:./../../Avvo-test-results/Lawyer/BVT/TestResults_A.html"

t.spec_opts << "--format documentation"
or

t.spec_opts << "--format=documentation"

t.verbose = true
end

[rajars2576]

c:/ruby/lib/ruby/gems/1.8/gems/rspec-1.3.1/lib/spec/runner/options.
ad_class': "documentation" is not a valid class name (RuntimeError)