sudo apt-get -y install ruby1.9.1
sudo apt-get -y install ruby1.9.1-dev
sudo gem install rubygems-update
sudo gem update
again i don't know what backbox is running im guessing 1.9.3 make sure you using the right ruby-rvm 1.9.3 is faster and more affective or should i say efficient at loading the modules faster
Metasploit do let modules out sometimes with some import errors and have many a time had to fix them within the modules
but in this case that was'nt the issue !!!!
AND while I'm on the point !! if you having an issue with a certain gem remember while it will install the latest gem by the above You may also have an early version that will cause a conflict
example :
sudo gem install nokigiri --version "number"
sudo gem uninstall nokigiri
this will then ask .. if there is two installed do you want to remove x or x & y { versions } .. example !! then you can remove both then and use the below to update to the latest
sudo gem install nokigiri
to install the latest
and etc etc blah blah gem dep etc etc and look up man gem etc .. search for whats in the gems database etc etc ..ok im getting bored listening to my self now !!!
I might as well finish what I started
so if you need to get lets say a version that is the latest or whatver
sudo gem search --remote nokigiri | sort -n | tail -1
etc etc you can use grep , awk ,sed what ever you like or makes you happy
But if you have an issue post and the guys will help !!!!