System Services -> Documents & Sync using all my data

After I upgraded I got a notice from my provider that I've used up all my cellular data... I'm on prepaid and buy it in blocks and had just recently bought more. Anyways having a look it appears that System Services -> Documents & Sync is using up all my data. I bought some more data and reset my statistics and it went through another 20 megs within a minute or two. So I've disabled cellular data for now...