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So if you had any trouble using that feature before, give it a shot again it should be working better. We've had success with at least three different folks now for whom it didn't used to work (or stopped working) and now works again.
If you're unfamiliar with the feature, check it out then try it out, it's pretty handy. It allows you to send the URL of a pen over to a mobile device so you don't have to type it out.