There is a Enterprise Application having multiple module, different team handles those modules, ATG is also kind of module in the application. Other team members dont have knowledge of ATG, they just include jsp provided by ATG team by tiles. How to add ATG module in that Enterprise Appication.
There could be different types of approaches and you would have to weigh them in order to decide which is best suitable in your environment. A quick way could be like creating a standalone ATG EAR assembling your ATG module so that you can refer and use that ATG EAR from your other modules just like any standard EAR. Standalone ATG EAR will pack everything related to ATG in itself and will not refer to ATG installation. Another way can be is to instrument everything required for ATG within an existing module like adding the PageFilter, NucleusServlet etc. (refer to any existing web.xml of an existing ATG application). You would also have to hook atg_bootstrap.war and atg_bootstrap_ejb.jar as well. All of this may require many other tweaks also in order to successfully integrate whole of ATG and to start it when you start rest of the modules. I think better would be to create standalone EAR and use it.