Was playing here to test  through the last parts of 0.915 before you patch it up, and was fighting a darkling shaman who cursed my hero repeadetly.

I noticed that if I was cursed, and then used the "defend" option. I would end up at 5 defense while defending (no shields or nothing).
But if I was defending, and a curse hit me, I would go to 0 defense while defending.

Ok im a bit lazy atm. so youll get a screenie from mr dropbox.
https://www.dropbox.com/s/vv3u64pwqwzf35u/Curse.jpg It does say 0 defense when I hover my mouse over my hero, but the detailed system shows this after I defended, but was cursed... then went out of defensive stance.

Sincerely
~ Kongdej