someone posted it on the battlenet forum..
"
Since I can't write a support ticket about this issue I guess i have to make it public.
Class: Wizard
Repro:
Step 1: Select Teleport - Fracture. Bind it to a key
Step 2: Select Archon, tested with Improved Archon
Step 3: Hover your mouse over or near your charcter
Step 4: Press Teleport
Step 5: QUICKLY(!) Press Archon
Result: Character becomes Invulerable. No health loss at all, some effects like frozen don't work anymore.
Works in Softcore and in Hardcore. Needs a couple of tries to get it working, but once you have the timing it can easily be reproduced. This is pretty much gamebreaking, I hope to see a hotfix soon."