Install bittorrent with:
Code:
sudo apt-get install bitorrent
And then use btmakemetafile
Forgot the exact parameters for a right creation but just use either "man btmakemetafile" or just type "btmakemetafile" and it will show you a couple of options

I really forgot if it was bittorrent or bittornado, but pretty sure it was bittorrent so try the other one if the first one dosen't work