For those of you who don't want to reset their network settings, here is a new workaround:
1. Go to one of Onavo's apps (Extend, Count or Protect)
2. Enter the settings menu (on the right upper corner)
3. Turn 'Service Status' off and install the prompt profile
This will install a profile that prevents from 3G data to go through Onavo's servers.
I hope that you'll find this solution better.