If any of you have a good idea how Archos could perhaps do it, even though you don't have access to the Archos OS source code, perhaps you could post suggestions here.
Sure I have a suggestion: my contract rate is ┬ú3500 per week. I can think of all sorts of approaches, but I would need to be paid for that kind of work
Which Java virtual machine code should Archos add to the firmware? Can Archos rather easilly make sure that executing those applications stays secure and perhaps even requires authentication through a cryptographically signed database connection that allows the verified applications or verified ported versions of certain aplications only to be installed.
I don't think there is any choice of JVM. It has to be the Google Dalvik thing, that's part of the deal. The only choices left to OEMs, so far as I can see, concern how to integrate the Dalvik I/O and UI classes with the operating environment.
As I've said before, I'm sure that if Archos wanted to put a `real' JVM on their devices (e.g., J2ME Personal Profile), Sun Microsystems would fall over itself in its haste to help out. It wouldn't even be very difficult -- I was able to get the experimental KVM implementation of J2ME PP working (almost) on the PMA400 under Qtopia. The new units don't use Qtopia, but they have at least a rump of Qt/Embedded, so I doubt it would be a massive undertaking.
But Archos don't _want_ to do it. It's not that they _can't_ do it.