I would trust the package.
I don't personally trust those online websites - especially LiveStrong and Sparkpeople. I don't trust them because it seems that every calorie count was posted by a person just like you or me, and they are never accurate. I know they aren't because I have the same products at home and the counts don't always match (like you are saying), and sometimes I check a sandwich from a chain and the chain website has something totally different, and sometimes, it just plain doens't make sense or you see 3 or 4 entries with the same food but different counts.
It might just be me who doesn't trust those sites...I've noticed whenever I ask for a calorie count here I just get responses to go check LiveStrong.
I think Livestrong is an OK guide, but I wouldn't say everything is entirely accurate.