how to override [] brackets in ruby?

I am writing an Ajax request form with Ruby on Rails using a collection_select tag that looks like this:

<%= collection_select("Jobs", "clearance", @allClearances, "clearance", "clearance", {:prompt => "Select a Clearance"} )%>

Ruby then builds an HTML select tag with id = "Jobs_clearance" and name = "Jobs[clearance]"

I want to send the parameter to my controller, which looks like this:

class JobsController < ApplicationController
  def foo
    @clearance = params[:Jobs[clearance]]
  end

Unfortunately, Ruby only reads ":Jobs" as the symbol instead of ":Jobs[clearance]"
Is there a way to escape the []'s? backslash isn't working.