Make my Mod useable in a multiplayer server.

[hernandez...@gmail.com]

Hello Jimmy, 

I followed the instructions in the book so I was able to make a Mod and I built the .jar then it worked in Minecraft after I put it in the mods folder. However, it only works for single player. Is there something I should do to make it work for a multiplayer server? I noticed that when i play in  a multiplayer server, my custom blocks appear in the inventory, however when i try to place them, they disappear as soon as I place them. And my custom commands don't work. 

Thank you in advance for any guidance :)

Best,

Sara.