I became partially soul trapped to avoid being a vampire since i'm also werewolf. I didn't go directly to find Valerica, saw a floating gem but it was not the good one, fight a guardian and then in the middle of the fight the vision changes, I have a message I have feed enough, etc. I'm a vampire now on top of being weakened and still a werewolf too...A bug or the guardians give you vampiris too? What a mess!

Something sounds off here. Doesn't lycanthropy confer an immunity to diseases, including vampirism?

Maybe the Dawnguard only checks if you are vampire when you hire Gummar and Sorine ? i'll see it for myself soon But I want to cure vampirism anyway, I don't like at all the Vampire Lord gamaplay (too strong and yet too impractical, that's too much ).

Sure does.

Apparently, in another thread (http://www.gamesas.com/topic/1401398-both-vampire-and-werewolf/) it is revealed that there's some bug wherein you can be both at the same time.

Huh! Odd. a furry, winged, Werewolf-Vampire creature. That's a strange image, lol.

Sounds like a pain-in-*** to manage, too.

I'm also envisioning all sorts of weird scripting errors and glitches it'll probably cause at some point... tangled webs of code and angry gamers...