Has any one heard of poloneto sweepstakes? and if so are they valid or a scam?

i work in a residential facility and one of our residents got this letter and check for 1,996.00$ and i'm trying to find out if its a scam or valid

Has any one heard of poloneto sweepstakes? and if so are they valid or a scam?
i am telling you from experience do not cash it, i put mine in the bank last monday for a 2,630.00 cashiers check, made 3 loan payments and now i get a call today from my bank saying i am in the miinus and owe for all the 3 loan payments, plus i put my paycheck in yesturday and they took that too. i am so upset, i dont know what to do, but it is called oz lotteries, if you know what i can do, please let me know. thankyou
Reply:scam, scAM,SCAM,SCam,scam!!!
Reply:Scam... oh yeah.