I\'ve been working with Eclipse 4.2 (Juno release 20120920-0800) on OS X 10.8.2 for a few weeks now, building apps for Android 3.0 and above. I have a quad core i7 MacBook P
I'm on a Mac and using ADT, can confirm that the following worked for me.
cd workspace/.metadata/.plugins/org.eclipse.core.resources/.projects
rm -rf *
No amount of restarting the Eclipse, or rebooting the Mac was helpful. It seems that Eclipse gets into this stage because of stopping abruptly. I had to force boot my Mac and this issue seems to be happening since then.