JBoss-Seam-Int is:

1) MC part
  - currently Seam specific deployer
  - hopefully in the future some other optimization

2) AS part
  - JBossAS custom Seam impl; e.g. VFSScanner instead of URLScanner
  - for 2.1.1. we're thinking of optimizing how resources are looked up
   e.g. using JBoss5 existing lookup mechanisms (we already do it for EJB3)
  - MC components can be part of Seam components
   e.g. getting underlying TransactionManager from MC

MC part will not change a lot.
Where AS part will grow with Seam's changes.
e.g. introduction of hooks for resources lookup optimization

How this comes into JBossAS project is under the same name = jboss-seam-int.
I then during the JBossAS instance build, place the in the right places:
  - MC part goes into JBossAS deployers
  - AS part goes into newly created lib-opt directory

Once you deploy your Seam app,
Seam+MC deployer knows which deployments are Seam deployments,
and adds the Seam+AS part into deployment's classpath.
Seam has a list of custom classes and if they are present they are loaded.
e.g. VFS Scanner is checked, before you fallback to URLScanner