As currently implemented in MegaMek, 'Mech spikes don't quite live up to the TO rules -- most notably, they only check for breakage after physical attacks when it should be any old source of damage and the bonus spike damage inflicted by a charging unit so equipped is apparently determined by random impact rather than counting the attacker's torso-mounted spike clusters as per the formula in the book.
I've got a fix for this in the works and it seems to be coming along nicely so far, but I want to test, and tinker for a while longer yet (and ideally wait for some revelant rules questions to be answered, too -- especially considering spike vs. spike interaction because that could require some more changes in multiple places in the code if it works as I half suspect) before I'm ready to declare it good to let loose on the repository.
I'm going to change this to accepted since you're working on it. Also going to put it into post-stable since it's not clear when your fix will be ready and it's not something that is required for stable. If it's done in time, feel free to put it into the stable milestone.