Item delivered by USPS can't be tracked?

I had ordered an iphone 4 days ago on ebay.
Currently this is what the USPS status site reads:

YOUR LABEL NUMBER LK079015769US
SERVICESTATUS OF YOUR ITEM Electronic Shipping Info Received
DATE & TIMELOCATION September 11, 2012
FEATURES International Letter
and yes the seller dropped it off to the post office
the website STILL has not updated, nor have I received the package. It is priority mail, shouldn't it have updated by now?

Added (1). Oh, the track information has just been updated on the USPS site: You entered: LK079015769US
Delivery status information is not available for your item via this web site. A return receipt after mailing may be available through your local Post Office.
Does it mean the item is in my country now? And the item can't be tracked in the express of my country

Try the same tracking No. On FedEx tracking. Sometimes, especially through Amazon or Ebay, the order will claim it was sent via USPS but utilizes FedEx instead due to requirements for delivery. (I.E. If you have priority, 3-day, or next day shipping.) Otherwise, call USPS and report that there's no tracking info.

It is quite possible that since the package is small that it did not go through the parcel sorting machines that read the barcode. Small packages like a phone would get sorted by hand and not scanned. It has probably left the city of origin and is on an airplane on it's way to you. Your package is not sitting somewhere, but has been dispatched as normal. Just the barcode did not get scanned.