Using gtalk with my Android phone and the Openfire gtalk plugin for a few months now, I am pretty impressed by the way gtalk forwards all messages to all resources. Its simply and easy: Start an converstation on the phone and switch over to the desktop. All messages are there. :-)
It's sad that this feature isn't implemented in Openfire and it's even sadder that there is no issue for this feature request yet (at least I found none). Please devs, create one and let the community vote.
It would be nice to see this feature as a per user setting. Which could be changed via a remote server command.