Symfony routing.yml, generate URL

Hi all there are 2 modules
company and post
post is described as:

post:
class: sfDoctrineRouteCollection
options: { model: BlogPost }

Don't quite understand how to make a route thus, to get a url of the form:
/company/24/mycompany/show/post/13

If you do so (will not work of course):

post_new:
url: /company/:id/:title/show/:post/:post_id
param: { module: company, action: show }
class: sfDoctrineRoute
options: { model: BlogPost }

Then you can specify only 1 model, and how to make so that to generate the url used 2 models?

Thank you.