Legality questions

[Mi@ow]

Hello everybody !

First I have to apologize for my bad english; Im a Swiss student and learn it at school ^^
I love the entire project and idea, but have some questions about the "legality side" of that;

1. Did you write the entire code of the minecraft server or did you "translate" the existing one and makes the adaptations that make it possible to work ?
   
2. Did you ask, and in this case did you get a kind of authorisation from Mojang to do this C++ adaptation ? (Or is there any legacy that tell that Mojang have nothing to tell you ?)
   
3. Can we legaly use MCServer to create Minecraft server (or do we have to ask Mojang first) ?
   
4. In the case where we run a MCServer server, are we ruled by the Minecraft's servers rules ?
   

I know this sounds like accusations but I can assure you it's not ! ^^
I juste had a Minecraft server with some friends of my school and we wanted to join the C++ side of the force (we all master the C++, and more than Java), but with all the EULA stuff, we don't know what we are allowed to do (we wants to stay legal all the time...).

A really huge thanks for all who will answer !
(And again sorry for my vocabulary x/ )