I like the idea of somehow making sure that the userids (and perhaps other ids as well) are globally unique for a person (at least to that one application). In the future this could even evolve to a system where, when a user couples for instance his myspace account to his hi5 account, the same userid would be returned for that user across the two containers.

Then again, this would need some extra security: when a container claims that user "myspace_1234" has logged in, there is little way for the application of verifying that claim.

So probably the best way to go right now is indeed to just prepend the containername to the id on the serverside of your application (where the containername can be read securely).

On 12/23/07, hobnobLover <hobn...@gmail.com> wrote: