ITs like when you try to activate Whatsapp for the first time. Don't you get a message with an activation code..? that messge come from out of the country which means its international. But how did that message know that it needs to come because you're trying to activate whatsapp..? It knows because whatsapp made your phone send an international message to whatsapp server requesting that activation code. Zain charges 50 fls for any international message. But they say they remove that charge and you don't pay but i don't really trust them.
Honestly, i highly doubt zain will fix the imessage issue cause its in their benifit to keep it broken. And i highly advise anyone with this problem to try and go to zain building and address this issue. As for me, ive already went their and tried and they promised they will call me or get back to me but they haven't so far. So I'm giving them till after Ramadhan and then i'll be changing my carrier to viva