Originally posted by srankmissingninIf you look at the panels he didn't have it in one and the next he had it. So he had it concealed where he could reach it. Just like he just as easily could have concealed a silver stake or knife.
That's making the assumption that he took out the vial after Wolverine pinned him. We don't know when he took it out, all we know is that he had it when he said "I may be half-vampire, but I ain't dead."... and besides, I doubt he was carrying it in his shoe.