Rails 3.1, installazione di Capybara-Webkit, non è riuscito a costruire un'estensione nativa GEM, cosa fare?

Question

Sto cercando di installare Capybara-Webkit (0.8.0), ma ricevo l'errore di seguito, posso aiutare qualsiasi corpo, sono su Ubuntu 11.10.

Installazione di Capybara-WebKit (0.8.0) con estensioni native Gem :: Installer :: ExtensionBuilderror: Errore: Impossibile costruire l'estensione nativa GEM.

    /home/sam/.rvm/rubies/ruby-1.9.3-p0/bin/ruby extconf.rb  /usr/bin/qmake /usr/bin/make cd src/ && /usr/bin/qmake

/home/sam/documents/ror/course_builder/cdpath=/ruby/1.9.1/gems/capybara-webkit-0.8.0/src/webkit_server.pro -pro -spec/usr/share/qt4/mkspecs/linux-g ++- o makefile.webkit_server/usr/bin/make cd src/&& make -f makefile.webkit_server make [1]: immettere la directory /home/sam/Documents/RoR/course_builder/CDPATH=/ruby/1.9.1/gems/capybara-webkit-0.8.0/src' g++ -c -pipe -O2 -Wall -W -D_REENTRANT -DQT_WEBKIT -DQT_NO_DEBUG -DQT_WEBKIT_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_CORE_LIB -DQT_SHARED -I/usr/share/qt4/mkspecs/linux-g++ -I. -I/usr/include/qt4/QtCore -I/usr/include/qt4/QtNetwork -I/usr/include/qt4/QtGui -I/usr/include/qt4/QtWebKit -I/usr/include/qt4 -I. -o RequestedUrl.o RequestedUrl.cpp make[1]: g++: Command not found make[1]: *** [RequestedUrl.o] Error 127 make[1]: Leaving directory /home/sam/documents/ror/course_builder/cdpath=/ruby/1.9.1/gems/capybara-webkit-0.8.0/src 'make: * Sub-SRC-WebKit_Server-Pro-Make_Default-ordinato] Errore 2

make cd src/ && make -f makefile.webkit_server make [1]: immettere la directory /home/sam/Documents/RoR/course_builder/CDPATH=/ruby/1.9.1/gems/capybara-webkit-0.8.0/src' g++ -c -pipe -O2 -Wall -W -D_REENTRANT -DQT_WEBKIT -DQT_NO_DEBUG -DQT_WEBKIT_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_CORE_LIB -DQT_SHARED -I/usr/share/qt4/mkspecs/linux-g++ -I. -I/usr/include/qt4/QtCore -I/usr/include/qt4/QtNetwork -I/usr/include/qt4/QtGui -I/usr/include/qt4/QtWebKit -I/usr/include/qt4 -I. -o RequestedUrl.o RequestedUrl.cpp make[1]: g++: Command not found make[1]: *** [RequestedUrl.o] Error 127 make[1]: Leaving directory /home/sam/documents/ror/course_builder/cdpath=/ruby/1.9.1/gems/capybara-webkit-0.8.0/src 'make: * Sub-SRC-WebKit_Server-Pro-Make_Default-ordinato] Errore 2

I file GEM rimarranno installati in /home/sam/documents/ror/course_builder/cdpath=/ruby/1.9.1/gems/capybara-webkit-0.8.0 per l'ispezione. Risultati registrati a /home/sam/documents/ror/course_builder/cdpath=/ruby/1.9.1/gems/capybara-webkit-0.8.0/./gem_make.out un errore si è verificato durante l'installazione di capybara-webkit (0.8.0 ) e Bundler non può continuare. Assicurati che gem install capybara-webkit -v '0.8.0' riesce prima del raggruppamento.