It's a bit strange, but upload doesn't go to the setted limit...
When i was on emule with Windows all went good...even with 3 open slots i came up to 37 KB/s upload....
But now, setting even 5 KB/s per slot it's very unstable...
See the pic:

I know it depends much from downloading clients....but it's strange....
Exists something like packet priority or something else?