i have install ruby 1.8.5 (2006-08-25) [i386-mswin32] and also install rails..... according to tutorial http://allaboutruby.wordpress.com/2006/01/09/installing-rails-on-windows-step-by-step-tutorial/

and according to 'Rails in action' section of the tutorial when I configure 'database.yml' file like ,

development:
adapter: mysql
database: firstproject
username: root
password: password
host: localhost

and try to start the server by command "ruby script/server" the following error occure, how I will solve it,

=> Booting WEBrick...
F:/Ruby/installation/ruby/lib/ruby/1.8/yaml.rb:133:in `load': syntax error on li
ne 17, col 2: ` host:localhost' (ArgumentError)
from F:/Ruby/installation/ruby/lib/ruby/1.8/yaml.rb:133:in `load'
from F:/Ruby/installation/ruby/lib/ruby/gems/1.8/gems/rails-1.1.6/lib/in
itializer.rb:459:in `database_configuration'
from F:/Ruby/installation/ruby/lib/ruby/gems/1.8/gems/rails-1.1.6/lib/in
itializer.rb:181:in `initialize_database'
from F:/Ruby/installation/ruby/lib/ruby/gems/1.8/gems/rails-1.1.6/lib/in
itializer.rb:84:in `process'
from F:/Ruby/installation/ruby/lib/ruby/gems/1.8/gems/rails-1.1.6/lib/in
itializer.rb:42:in `send'
from F:/Ruby/installation/ruby/lib/ruby/gems/1.8/gems/rails-1.1.6/lib/in
itializer.rb:42:in `run'
from ./script/../config/../config/environment.rb:13
from F:/Ruby/installation/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_re
quire.rb:27:in `gem_original_require'
... 7 levels...
from F:/Ruby/installation/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_re
quire.rb:27:in `gem_original_require'
from F:/Ruby/installation/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_re
quire.rb:27:in `require'
from F:/Ruby/installation/ruby/lib/ruby/gems/1.8/gems/activesupport-1.3.
1/lib/active_support/dependencies.rb:147:in `require'
from script/server:3

please any one help me !!!

thank you ....