How can folder architecture be organized in symfony 1.4?

Question

symfony

Hi all! Please tell me how you can organize the folder architecture on symfony 1.4
The goal of the project is multi-site (such as separate applications) and a separate common admin panel with common management and common bundles. And that, something while badly I imagine it.
Something like -
sites/
---- site1/
-------- config/
-------- modules/
---- site2/ ...
---- site3/ . ..
backend/ # this is a common admin panel that manages all databases at once.
modules/ #general modules here
libs/
index.php # front-controller and here the condition for selecting a site/folder from the domain
Approximate folder architecture .. Has anyone come across this? Or maybe there are better solutions?