How to Use ActiveResource with Shallow Nested Routes?

I have a Rails application that has a Company resource with a nested resource Employee. I'm using shallow routing, so to manipulate Employee, my routes are:

GET     /employees/1
PUT     /employees/1
DELETE  /employees/1
POST    /companies/1/employees

How can I create, read, update, and destroy Employees using ActiveResource?

To create employees, I can use:

class Employee < ActiveResource::Base
  self.site = "http://example.com/companies/:company_id"
end

But if I try to do:

e=Employee.find(1, :params => {:company_id => 1})

I get a 404 because the route /companies/:company_id/employees/:id is not defined when shallow routes are used.

To read, edit, and delete employees, I can use:

class Employee < ActiveResource::Base
  self.site = "http://example.com"
end

But then there doesn't seem to be a way to create new Employees, due to the lack of the companies outer route.

One solution would be to define separate CompanyEmployee and Employee classes, but this seems overly complex.

How can I use a single Employee class in ActiveResource to perform all four CRUD operations?