Rings a bell if feign death is resisted. Also displays a very noticeable feign resist error message. You may not hear the bell if your computer is old, cheap, or slow, or if there is a lot of combat. Hearing the bell depends on the number of available sound channels and the number of sounds occurring at the same time.
I removed a really old no-longer-needed workaround to hear the bell.
Tested and works perfectly with WotLK.