I believe TV 0637 is only available as an upgrade (is not built into any of the remotes).
I'm not sure of the rule, costs, or limits, but under some conditions you can mail the 15-2104 in to have an upgrade code like TV 0637 added to it. Unless that is a lot easier than I expect, I recommend a different method.
You can buy or build a JP1 cable that allows you to install such upgrades yourself from a Windows parallel port. There is a Yahoo group with all the (freeware) programs and files (and helpful other users).