Healbot and Undeads problem.

Hi all, it's the first time i have a problems with healbot and i can't understand why.

Recently i entered in the Outland server, created a Blood Elf hunter and a Warlock too, everything worked fine. But when i wanted to play with a friend, both created an Undead and problems appears. The bars are empty, no names appears and they didn't move neither when our life falls.

I disabled all other addons just for try if it was a problem with anyone of them (and i use allways the same addons). Tryed to reset healbot, and nothing worked.

The problem (for the moment) only happens with Undeads.

Any solution?

This is a Capture from the healbot problem: http://oi63.tinypic.com/znr4fc.jpg

Thanks in advice.

EDIT: This appeared when i activated Lua Errors: http://oi66.tinypic.com/8vmw.jpg