What steps will reproduce the problem?
1. Enter an instance such as Naxx or Tempest Keep(one that causes you to resurrect to full health at the Spirit Healer, rather than as a spirit to run to your body)
2. Die
3. Choose "Release Spirit"

What is the expected output? What do you see instead?
Health bar of me (most of the time) and other party members (rarely) should show with full health, yet instead they show as 0.  Mana however shows correctly (when applicable).

What version of the product are you using?
r259 (Just downloaded r260 and am about to install it)

Do you have an error log of what happened?
This does not produce an error.

Please provide any additional information below.
It doesn't happen every single time when in Naxx, but I do remember it happening every time in TK when running it, and pretty much only to my player's health bar. Now that I think about it, I don't remember it happening on any 5-man instance in TK area, so maybe it's only related to Raid Frames.  I've been running Naxx on my Shaman mostly, and what I do to get my health bar back to 100% is just do some heals (they heal for 0, so it's not a Blizz bug from what I can tell).