From a NWN rule I can't see why there should be a conflict. But having never played a druid - then I wouldn't be able to say from experience. It could also just be a bug. (Sorry - I can't help you more)
The only reason I can think of is that your animal empathy isn't terrible high with only 3 druid levels and it perhaps was as a straight druid in NwN/SoU?
Or perhaps, there are no animals to speak to at all, but only monsters, in HotU
