Forum:How to add mods to multiplayer?

Howdy =}

We're running a multiplayer server for a few friends. I would like to add some of the ported mods from mc port central. I know how stunningly easy it is to add the mods to the server itself (yay drop things into a folder) but don't I have to edit the client too? Won't I need to have the other players also update their clients? Or no? I've been looking for videos or how tos and am coming up empty. Help?