Cannot repeat from a remote user unless you were previously subscribed

Imagine that you run your own StatusNet install, and do most things over OStatus -- then, dents from identi.ca (for example) won't appear or be given IDs by your StatusNet install until you subscribe to the relevant user. However, back dents are not imported; only dents from the time you subscribe on are included. Therefore, they don't get assigned notice IDs, and therefore they can't be repeated by way of the repeat API. This is an issue if, for example, you browse around the public timeline on identi.ca and find a notice you'd like to repeat, but you don't yet follow that user. The repeat would have to be done manually, and without the benefits of the repeat API.

(component on this may be inaccurate; repeats were the specific thing that this came up with, but it is a more general issue)