启动rails服务器时出现以下错误。
/Users/joy/.rvm/gems/ruby-1.9.3-p194@project/gems/activesupport-3.2.16/lib/active_support/dependencies.rb:251:in `require': cannot load such file -- systemu (LoadError)
from /Users/joy/.rvm/gems/ruby-1.9.3-p194@project/gems/activesupport-3.2.16/lib/active_support/dependencies.rb:251:in `block in require'
from /Users/joy/.rvm/gems/ruby-1.9.3-p194@project/gems/activesupport-3.2.16/lib/active_support/dependencies.rb:236:in `load_dependency'
from /Users/joy/.rvm/gems/ruby-1.9.3-p194@project/gems/activesupport-3.2.16/lib/active_support/dependencies.rb:251:in `require'
from /Users/joy/.rvm/gems/ruby-1.9.3-p194@project/gems/macaddr-1.6.2/lib/macaddr.rb:23:in `<top (required)>'
from /Users/joy/.rvm/gems/ruby-1.9.3-p194@project/gems/activesupport-3.2.16/lib/active_support/dependencies.rb:251:in `require'
from /Users/joy/.rvm/gems/ruby-1.9.3-p194@project/gems/activesupport-3.2.16/lib/active_support/dependencies.rb:251:in `block in require'
from /Users/joy/.rvm/gems/ruby-1.9.3-p194@project/gems/activesupport-3.2.16/lib/active_support/dependencies.rb:236:in `load_dependency'
from /Users/joy/.rvm/gems/ruby-1.9.3-p194@project/gems/activesupport-3.2.16/lib/active_support/dependencies.rb:251:in `require'
from /Users/joy/.rvm/gems/ruby-1.9.3-p194@project/gems/uuid-2.3.7/lib/uuid.rb:14:in `<top (required)>'
from /Users/joy/.rvm/gems/ruby-1.9.3-p194@global/gems/bundler-1.5.3/lib/bundler/runtime.rb:76:in `require'
from /Users/joy/.rvm/gems/ruby-1.9.3-p194@global/gems/bundler-1.5.3/lib/bundler/runtime.rb:76:in `block (2 levels) in require'
from /Users/joy/.rvm/gems/ruby-1.9.3-p194@global/gems/bundler-1.5.3/lib/bundler/runtime.rb:72:in `each'
from /Users/joy/.rvm/gems/ruby-1.9.3-p194@global/gems/bundler-1.5.3/lib/bundler/runtime.rb:72:in `block in require'
from /Users/joy/.rvm/gems/ruby-1.9.3-p194@global/gems/bundler-1.5.3/lib/bundler/runtime.rb:61:in `each'
from /Users/joy/.rvm/gems/ruby-1.9.3-p194@global/gems/bundler-1.5.3/lib/bundler/runtime.rb:61:in `require'
from /Users/joy/.rvm/gems/ruby-1.9.3-p194@global/gems/bundler-1.5.3/lib/bundler.rb:131:in `require'
from /Users/joy/analytics/cappings/config/application.rb:17:in `<top (required)>'
from /Users/joy/.rvm/gems/ruby-1.9.3-p194@project/gems/railties-3.2.16/lib/rails/commands.rb:53:in `require'
from /Users/joy/.rvm/gems/ruby-1.9.3-p194@project/gems/railties-3.2.16/lib/rails/commands.rb:53:in `block in <top (required)>'
from /Users/joy/.rvm/gems/ruby-1.9.3-p194@project/gems/railties-3.2.16/lib/rails/commands.rb:50:in `tap'
from /Users/joy/.rvm/gems/ruby-1.9.3-p194@project/gems/railties-3.2.16/lib/rails/commands.rb:50:in `<top (required)>'
from script/rails:6:in `require'
from script/rails:6:in `<main>'