Cannot set single banwidth limit

[j4ckp0t85]

I don't know if this is an expected behavior or not. Anyway: if i try to set for example an upload limit and don't specify any value for download limit, i get an error (please specify a positive value).

It would be useful if the values could be pre-propulated for active limits setted on the client, but i don't know if it's possible for all clients handled.

Ps: i use transdroid interfacing with an rtorrent instance