I purchased an 8 GB Iphone 2 weeks ago but the battery is weak. It lasted for 2 to 3 hours and apple store replaced with a different phone today but I am wondering if the replaced Iphone is refurbished. I am still in the period of return date when I reported the problem and I assume they should replace it with new instead of refurbished. Can I find out by the serial number if the replaced phone is refurbished.