The biggest problem with a java mobile device is performance. No matter how you port it, there will always be a java layer between the the hardware and port. It would be just to damn slow to work as I know only too well with the media player I have on my Nokia 6230.
Sorry for going off-topic but what about the possibility of a future standalone port of smartphones/PDA's? Since they can run a version of linux (and other os's as well ie Symbian, Microsot CE, Palm Os? but not sure if they have the appropriate C compiler) it would be possible to port rockbox over to them?
I've found a link for linux smartphones currently on the market. I've checked the details of a few but doesn't give much details about the hardware specs
http://www.linuxdevices.com/articles/AT9423084269.htmlThese phones are far too expensive at the moment for mainstream use but in a few years it may be a different story.
Before I get flamed I think this would be a different project from rockbox which I think has done a wonderful job of breathing life into DAP's whose original firmware had put them into mediocrity.