You know, that theres a Bugsection on the Forum? You are definetly wrong here.
And try to install one Mod after another, because elsewise you will get massive ID-Conflicts. Or simply set all the other nonrequired Mods off in the Modloader.cfg
IC² is a Mainmod so if you want to play it SMP you should not set it's BlockID's (and also not BC's)