If you're using SignPortals/Portals' purple goo feature, whenever you go through one, if there is no NAME_nether, you will recieve warnings in the console.

The proposed fix is to dual monitor the event, Lowest and Highest, to determine if the location was changed by someone else. If it was, don't show the warning, if not, show it.

I've averted the knockback in the latest builds: http://multiverse.github.com/news/better-end-support.html

As this is primarily aesthetic preference, and we've been discussing elsewhere (#21) about the appropriateness of those messages to begin with, I'm pushing to 2.3 for now.