I note that the Detect Magic spell and Detect Undead spells are fairly similar in general function.
It is only when you look up the Spellcraft skill that you note that this skill can be used in conjunction with Detect Magic so that you can determine more about a magical item.
This is done by analysing the aura of the item which can actually be seen through obstructions, though you need to be able thoroughly examine the object to determine its properties – by this I guess this means handle it.
Now given Knowledge Religion checks do not require you to handle the undead creature to determine what it is, which would probably not be a wise thing to day anyway... and is subject only to a skill roll, surely you can determine what the undead creature is by combining Detect Undead and the Knowledge Religion skill in a similar way.
I would think a skeleton’s aura looks fundamentally different to that of a vampire and not just in terms of strength.
What are your thoughts?