Spells: Cleric healing issue?

[Ashintar]

Cleric healing... wrong group member?

Ok so this is my first healing class, for about 10 levels now every once in a while I'll cast a heal on a group member and it will affect a different group member. I thought I had gone crazy the first few time it had happened but it keeps happening, unfortunately w/o any regular occurrence.

While I know I sound crazy, and people are going to say that they've been playing healing classes for ages now w/o an issue does anyone have any ideas on what kind of proof / data (or how to get it) I need to help track down my issue?

This happens with more than one spell, I probably first saw it on Greater healing or maybe even Healing, but it just happened on Superior healing too...