Torrent drad-and-drop function can't continue files?

[p.pavlov]

Hello. My problem is that when I try to make a file with the new "Drop files to send" function and I send the link to a friend, he always starts the download from the beginning, no matter if he has the exact same file in the exact same download folder. I thought it might be just my µTorrent, so I sent myself a torrent made the same way from his computer and got the same result.

Does anyone have a clue on how to fix this or possibly get around it? It looks like a bug to me.