How to use rails runner altogether with bundle install --without development test?

In my Capistrano recipes, bundle install --without development test is performed. Then I tried to run a script with:

bundle exec rails r scripts/my-script.rb

It complained about not finding a development-only gem dependency that is not even required by that script.

How am I supposed to call rails runner when bundler is run with --without development test?

Thanks in advance,

Rodrigo.