Use of mods in multiplayer

[dunndude]

Well me and a friend both installed a mod (same version of FOC) namely

 

http://www.moddb.com/mods/star-wars-clone-wars/downloads/star-wars-clone-wars-version-30

 

Now we went to one of the rooms and tried to join a game after finishing a FOC game, although we both had a version mismatch we both checked we had the same versions of evrything ect

 

Is there a way to prevent this or is it inherent in the mods?