Dead and Loathing It.

[Dalillama]

Originally Posted by Jason

Ethereal vampires are spirits in the Image of the vampire of folklore and popular mythology, meaning that whatever we believe should affect vampires would affect such spirits. "Holy water" (blessed by mundane religious professionals) has no inherent power in In Nomine, but such vampires could react to it as a Dread.

You might want to take a look at Moe Lane's take on the subject. It'll almost certainly provide inspiration, and it's worth a look regardless.