Forum: Rails deployment dependencies.rb:55:

while installing fedena in VPS i am getting this error can any one have
solution

root@server [/home/gicsms/rails_apps/fedena]# script/server
/usr/lib/ruby/gems/1.8/gems/activesupport-2.3.5/lib/active_support/dependencies.rb:55:
uninitialized constant ActiveSupport::Dependencies::Mutex (NameError)
        from
/usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:36:in
`gem_original_require'
        from
/usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:36:in `require'
        from
/usr/lib/ruby/gems/1.8/gems/activesupport-2.3.5/lib/active_support.rb:56
        from
/usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:36:in
`gem_original_require'
        from
/usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:36:in `require'
        from
/usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/commands/server.rb:1
        from
/usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:36:in
`gem_original_require'
        from
/usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:36:in `require'
        from script/server:3
root@server [/home/gicsms/rails_apps/fedena]# from
/usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:36:in
`require'/dependencies.rb:55: