/Gemfile not found

Hi,

I'm getting a strange behavior when trying to build a rake step, this is the console output

```
Capturing environment variables produced by 'rvm use 1.9.3'
$ bash -c export
$ bash -c "test -f ~/.rvm/scripts/rvm"
[reid-functional-tests] $ bash -c " source ~/.rvm/scripts/rvm && rvm use --install --create 1.9.3 && export > rvm.env"
Using /var/lib/jenkins/.rvm/gems/ruby-1.9.3-p448
[reid-functional-tests] $ /var/lib/jenkins/.rvm/rubies/ruby-1.9.3-p448/lib/ruby/gems/1.9.1/bin/rake cucumber BROWSER=headless /var/lib/jenkins/.rvm/rubies/ruby-1.9.3-p448/bin/ruby -S bundle exec cucumber --format pretty
/Gemfile not found
Build step 'Invoke Rake' marked build as failure
Finished: FAILURE
```

if you notice, the not found Gemfile is related to "/", not into the working directory as expected to be found.

So, to weird issues, crazy workarounds, I put a copy of the projects Gemfile on root (/Gemfile) and it works.

OBS: I'm using RVM Plugin to set ruby environment.

Regards,
Pablo Ramírez