/summon Zombie ~ ~1 ~ {CustomName:LumberjackZombie,CustomNameVisible:1}
doestn't crash
Edit:
I am trying to trace the bug. The following command still crashes my server:
/summon Zombie ~ ~1 ~ {CustomName:LumberjackZombie,CustomNameVisible:1,Attributes:[{Name:generic.followRange,Base:1000},{Name:generic.attackDamage,Base:0}]}
I think this would be a nice feature to be able to kill invulnerable mobs in creative, but not in survival. If Mojang would put this on the release note, I will be happy. I don't think this is actually a bug.
This works just fine so I'm guessing it is the Huge followRange that is crashing the server.
Hope I helped