I had the same kind of problem. At the time I was not a premium member of PayPal.
I had about 10 auctions about to be completed on ebay when I received an e-mail that my PayPal account was restricted. I was no happy since I was advertising PayPal in all my auctions. I also had a small balance at the time. I stewed for a couple of days but then signed up as a premium member. One day later, I got an email saying the the account restriction was a mistake and they were 'sorry for the first email'.