Change pseudo-absolute assets path in Rails 3

I tried every way I found, but I don't know how to do it.

Rails always write /assets/... and would like to have ./assets/ or assets/ because my application is in a subfolder, not in the root folder.

I tried with config.action_controller.asset_host = "." but Rails write http://./assets/

I tried with config.assets.prefix = "." but rails write /./assets/

Suppose that my application lives in: http://ift.tt/OXbkMi, with the default behaviour of Rails every path point to http://domain.com/ not to http://ift.tt/OXbkMi and I don't want to specify an absolute path, because that is not portable.

Check this as example: http://ift.tt/1q1jHH1