Error on run

[arcanelab]

With a successful installation, after running instiki, the following error message is displayed:

./config/../vendor/rails/railties/lib/rails/gem_dependency.rb:21:in `add_frozen_gem_path': undefined method `source_index' for Gem:Module (NoMethodError)
    from ./config/boot.rb:62:in `load_initializer'
    from ./config/boot.rb:126:in `run'
    from ./config/boot.rb:26:in `boot!'
    from ./config/boot.rb:139
    from ./script/server:3:in `require'
    from ./script/server:3
    from ./instiki:6:in `load'
    from ./instiki:6

Any help would be greatly appreciated!

[arcanelab]

OK, here's a quick solution:

sudo gem update --system 1.8.25

Details here.