The iPod mini, a 3.6-ounce portable music player, is based around a tiny 4GB hard drive,allows it to store up to 1,000 songs comes in five colors--silver, gold, pink, blue and green--and works with Apple's iTunes online music store.

Since that date, Apple has received more orders than it had planned for, said Greg Joswiak, vice president of hardware product marketing at Apple. The number of orders--which included more than 100,000 preorders, according to Apple--was high enough to outstrip the availability of the 4GB drive from its manufacturer.

Apple says it was forced to concentrate on filling orders from the U.S. market and to wait for greater availability of the drive in order to enter the international market, he said.

"We expected it to be a hit, but (demand) is turning out to be stronger than expected," Joswiak said. "U.S. demand is going to consume all the supply we had planned through June."

The 4GB hard drive at the center of the iPod mini came out in January, around the same time Apple announced the device. Its manufacturer, reported to be Hitachi, is still ramping up, so the supply of the drives has been limited, Joswiak explained.

Right now, "The (iPod mini) demand is consuming just about all the 4GB 1-inch drives being made," he said.