Nokia Yearly Promotion SMS Scam Texts

i received a SMS telling me that my number won R250.000.00. I had to buy R275 Vodacom airtime to activate my ticket. I did so, phoned the numer that were given to me by by the person on the phone. I was then told to pay R2800.00 for insurance before the money would be paid into my account. I had to phone a Mr Simon to get the details on where to pay the money, I told him taht I was a pensioner and that my pension would only be paid in on the 10 th of August 2011, he told me that by then my tiket would have expired, how can that be after I have paid my R270.00 airtime. Is this a SCAM or WHAT??????