Install sys-proctable in Ubuntu 10.04 64 bits

luan@luan-laptop:~$ sudo /opt/ruby/bin/gem install sys-proctable --platform x86-64-linux
Successfully installed sys-proctable-0.9.0-x86-linux
1 gem installed
Installing ri documentation for sys-proctable-0.9.0-x86-linux...
Updating class cache with 3248 classes...
Installing RDoc documentation for sys-proctable-0.9.0-x86-linux...