no warranty. the warranty is only activated if u subscribed the iPhone with the telco, as the coverage is partially provided by both telco and Apple. so the only assurance that u have is on your purchase of iPhone at the apple store (if it's DOA, mmm...not really can be called as a waranty actually).
and nope, even if the iPhone is officially in malaysia, the US iPhones that we r using now will not being covered by warranty. it's like buying an AP phone.

Touch wood la, really touch wood, but in my history of buying gadgets (any type, phones, laptops etc), I have never had to use my warranty. Normally they just work till I decide to change. I think that's the case with most people as well. So I am not too worried about the warranty part. TOUCH WOOD!! 

I heard that you can get ur Iphone fixed by apple Malaysia.. but you have to pay for it ..