less-rails gem not importing less files as expected

Question

I'm trying to include less in my rails 3 projects so that I can have a global.css.less file that looks like this:

@import "variables";
@import "app";

However, whenever I do that, app.less can't access variables defined in variables.less.

The problem is explained here:

https://github.com/christiannelson/less-rails-example

has anyone had this problem or know who to fix it?

thanks