Truthfully, I don't really know enough about OSGi to comment on how Seam might be incorporated into such a container.
However, I can point you to a response given by Alex Justin, Core Developer for
JBoss Microcontainer, JBoss AS 5, and Seam integration specialist, when asked the very same question in
this interview:
No, but OSGi support for the features of Seam (EJBs, JSPs, JSFs) is currently being worked on by the OSGi EEG. As this continues to develop we should start to see Seam begin to implement that support. For the moment we could perhaps provide similar fine-grained package version support for their POJO components using some MC + Seam hooks. This is actually similar to how they currently perform hot deployment.