I'm not sure what this error is. http://pastebin.com/Y2kfQ6kb It gets spammed many more times than what I have pasted into the pastebin, but pastebin has a file space limit :/.
I'm not sure. Let me check. The majority of the spam seemed to come from NoLagg, though, which I'm pretty sure is up to date. I'll check though... Speaking of NoLagg, why is it separated into seven different plugins? And for some reason, I'm only able to find the update on the main one so far...
I always try to look for a "simplepluginmanager" in the error. If you can find that it usually means there is a compatability issue and you need to update the plugin if you can