Unless the games code itself got released, there's no way we can "trick" this anymore, it's very obvious they disable mod's through a class in their internal code now. The only way we can get mod's in multiplayer (except for hotseat) is to wait until they finish working on it and release it themselves.
There's no real way around it, the matchmaking class is used for our internet/lan games to start, and that class is internal (a part we can't change) and I believe that's the class which is disabling the mod's when it's called. I have no proof aside from whenever I enable mod's just before starting an internet game, after clicking the start button there's a long delay, then it starts without mods (The delay is from the mod's disabling I'm sure).
Aww. That's sad to hear. Let's hope they release the code as they did for civ 4 so us happy hackers can fix such shortcomings. I can understand they refrain from releasing functionality that is not ready for use due to bugs or other issues, but for hard-core modders who are used to that it is no problem