Several fixes for this. http://www.tesnexus.com/downloads/file.php?id=29669 one of the latest.

I've added eyes.rar. Extract these textures to your data/textures/characters/eyes folder and you'll get the blue underworld looking vampire eyes.

There is also a madmole.rar Extract those to your meshes directory. To change your teeth to fangs you want there are two ways to do it.

Step 1
If you have a custom race, open the esp that came with the custom race using the CS.


Then procede to step 2.

If you are using a vanilla or stock race you will need to make a new mod with the CS. Just load oblivion.esm and then save as my_race.esp or whatever you want to name it. Then Click on Character the Race and select the type of race you have. Right click and then click duplicate from the sub menu. It should create the same name below it with a COPY0000 extension. This next step isn't needed, but click on it so it flashes and you can rename it. Get rid of the COPY0000 and just rename that part to Custom. So if you were originally an Imperial, name it to Custom Imperial. If you were a Redguard, it would be Custom Redguard, etc.

Step 2
Click on your new race (or custom race) from the Character/Race menu. Now click on the face data tab. Under Teeth Upper box, click on that then navigate to the teeth you want to use under data/meshes/madmole/UnholyDarkness/

You can pick from VampireFangsTraditional or VampireFangsTrueblood. Ok it and save your esp.

Once in the game, open the console and type "showracemenu" without the quotes. From there you can change to your new race and the teeth will be changed. Don't close the menus or your attributes will get screwed up. Just save the game now, and then load that saved game and your done.

Custom Race Eye Fix:
If you use a custom race that has eye troubles when you activate vampirism, then you need to edit your race. What I did was make my race use the stock eye mesh, then overwrite the one eye you want to use for your race. Then set the texturepath of the nif file to use the custom eye texture, then cut the custom eye texture in half so it only has one eyeball on the image.

Another way to do it would be to just set your race to use one of the default eyes and then mod the default eyes to use the eye texture you like. Alternatively, there are probably some eye mods that do not use dual eye textures, any of those would work as resources.

Are there any more mods like the one fable2 linked to? The eyes in that link are black, and I prefer something more yellow red. It did solve my problem, though, both for my custom race and the NPC vampires......it's just the eyes are solid black!