Hello,
I am having problem with OpenVpn and Zoiper on android, it seems that Zoiper randromly choses whether to send packets via OpenVpn tunnel or regular 3g/Wifi interface.
Usually it won't connect via VPN but sometimes it does. This mostly happens during the registration.
I linked the PBX server to VPN network, to try login via local adress, same thing sometimes it works sometimes it doesent.