I don't think that the variable 'vers' exists, taking version from
pre-populated hash instead.
Does not respond to :ivars, but relevant methods already exist.

You can test with gist.github.com/robsyme/5429320
Minor whitespace fix
Pulling in changes from pjotr

Merge remote-tracking branch 'pjotr/master' into rob-hackfest
Merge pull request #39 from robsyme/rob-hackfest

Fixing ivars method missing error