Ever wonder why Facebook can act as a portal and be on multiple sites at once? There are two components.
One is the iFrame that magic that allows Facebook to display apps that have pages from another site. The other component is server styled rendering engine that receives all requests and sends back pages.
The Portlet container on the other hand has none of this structure and thus you cannot take a Portlet server and try and morph it into a portal that servers both portlets and multiple site servlet apps as one platform, its not made for that purpose. A great deal of the 20,000 hours Facebook development team spent in 2004 were spent on coming up with this model.
