D3 can be vegan/synthetic, supposedly. Tropicana fortifies their juice with D3, and they swear it's suitable for vegans. There are several threads here on the subject. I emailed them back in like 2003 or 2004 and they said it was NOT vegan, but later, another member or two received a different answer.
It also makes a difference as to what country you're in, I think. I know that the calcium sources for American orange juice and Canadian varieties, of the same brand, are often not the same, for example.
The ones I pity are the ones who never stick out their neck for something they believe, never know the taste of moral struggle, and never have the thrill of victory. - Jonathan Kozol