title: Redmine (1.4.7) error in executing server in development mode
body: <p>While running redmine 1.4.7 in development mode using the command <code>rails s</code>, I have got error like below</p>
  
  
  
  <pre><code> /usr/local/lib/ruby/gems/2.0.0/gems/rails-2.3.15/lib/rails_generator/options.rb:32:in
   `default_options': undefined method `write_inheritable_attribute' for
   Rails::Generator::Base:Class (NoMethodError)
           from /usr/local/lib/ruby/gems/2.0.0/gems/rails-2.3.15/lib/rails_generator/base.rb:90:in
   `&lt;class:Base&gt;'
           from /usr/local/lib/ruby/gems/2.0.0/gems/rails-2.3.15/lib/rails_generator/base.rb:85:in
   `&lt;module:Generator&gt;'
           from /usr/local/lib/ruby/gems/2.0.0/gems/rails-2.3.15/lib/rails_generator/base.rb:48:in
   `&lt;module:Rails&gt;'
           from /usr/local/lib/ruby/gems/2.0.0/gems/rails-2.3.15/lib/rails_generator/base.rb:6:in
   `&lt;top (required)&gt;'
           from /usr/local/lib/ruby/site_ruby/2.0.0/rubygems/core_ext/kernel_require.rb:126:in
   `require'
           from /usr/local/lib/ruby/site_ruby/2.0.0/rubygems/core_ext/kernel_require.rb:126:in
   `require'
           from /usr/local/lib/ruby/gems/2.0.0/gems/rails-2.3.15/lib/rails_generator.rb:37:in
   `&lt;top (required)&gt;'
           from /usr/local/lib/ruby/site_ruby/2.0.0/rubygems/core_ext/kernel_require.rb:126:in
   `require'
           from /usr/local/lib/ruby/site_ruby/2.0.0/rubygems/core_ext/kernel_require.rb:126:in
   `require'
           from /usr/local/lib/ruby/gems/2.0.0/gems/rails-2.3.15/bin/rails:15:in    `&lt;top
   (required)&gt;'
           from /usr/local/bin/rails:23:in `load'
           from /usr/local/bin/rails:23:in `&lt;main&gt;'
  </code></pre>
  
  <p>I have spent about 2 hours for fixing it and got some references from this  <a href="https://stackoverflow.com/questions/11078723/undefined-method-write-inheritable-attribute-for-railsgeneratorbaseclass">link</a><br>
  and now am getting this error. How can I fix this?? </p>
  
  <pre><code>/usr/local/lib/ruby/gems/2.0.0/gems/rails-2.3.15/lib/rails_generator/generators/applications/app/app_generator.rb:7:in `&lt;class:AppGenerator&gt;': Use RbConfig instead of obsolete and deprecated Config.
  /usr/local/lib/ruby/gems/2.0.0/gems/rails-2.3.15/lib/rails_generator/generators/applications/app/app_generator.rb:7:in `&lt;class:AppGenerator&gt;': Use RbConfig instead of obsolete and deprecated Config.
  /usr/local/lib/ruby/gems/2.0.0/gems/rails-2.3.15/lib/rails_generator/generators/applications/app/app_generator.rb:7:in `&lt;class:AppGenerator&gt;': Use RbConfig instead of obsolete and deprecated Config.
  undefined method `camelize' for "app":String
  </code></pre>