Apple's iPhone 4 smartphone has been sold out in Australia. In spite of a number of telecommunications companies saying that they expect new stock to arrive "over the coming days," Apple announced that it expects a delay of three weeks for the shipment of new orders.

Apple and it's suppliers have been struggling with the demand for the device worldwide.

Some people are taking advantage of the shortage. On eBay, the online auction, people put up their iPhone 4s for sale for a markup of up to 50 percent. The going rate for the smartphone on the Web site comes to at least $1300.

The 16GB and 32GB versions of the iPhone 4 cost $859 and $999 when bought outright from the Apple Store. The company says on its Web site that new orders would be delayed for three weeks, adding that stores in Australia have already run out of stock.

Optus, the telecommunications company, believes otherwise. The company, which ran out of iPhone 4 models on the weekend, said it would be providing regular stock updates to customers through its website.

"We expect to receive shipments of stock over the coming days and an outlook on further supplies from Apple shortly," the company said.

Thousands of people, some of whom have waited in line for around 24 hours, went to midnight launches across the country for the iPhone 4. On its Australian Web site, Apple advertised the free case program for the iPhone 4. Users who purchase the device before September 30 can get the bumper case by downloading the "iPhone 4 Case Program" app from the App Store.