Monster Hunter Portable 3rd (HD Ver. or not)

[schrade]

As the title says, we have a problem to play together. We tried Hamachi and Evolve, but nothing, well not really nothing, we managed to see each other in the gathering hall but when we try to start a quest, just two of us are in and the other one alone. We tried the "speed trick" too, just to be sure, still nothing.

Any idea of what are we doing wrong ?
Also my two friends are playing from the same house.

ps. sorry for my bad english