Consumers still looking to buy one of Hewlett-Packard's new Slate 500 devices will have to wait awhile.

Only three weeks since its debut, HP's new tablet is on back order, according to a notice on the unit's order page. The notice says the tablet is scheduled to ship in another six weeks, and a person in HP's sales department confirmed that it would be shipping on December 27. This means that people who place new orders for a Slate 500 won't be able to get one in time for the holidays.

HP has attributed the delay to "extraordinary demand" for its new tablet, but that may not be the full story, at least according to one report.

Citing an insider tip, Engadget says that HP reportedly only planned to manufacture 5,000 Slate 500s. When the company received orders for 9,000 units, it was forced to rehire workers to ramp up production again. Engadget further says that HP is shaving $100 off the tablet's $799 purchase price for customers now forced to wait.

E-mail and a phone call to HP's press relations seeking comment were not returned.

The Slate has gone through a bumpy birth. HP first teased a quick glimpse of the tablet at CES 2010 in January, which it followed up in early April with a video of the device after Apple's iPad had hit the market. But when HP acquired Palm earlier this year, reports came out that the tablet might be put on the back burner.

In July, details about the Slate surfaced on HP's Web site indicating that the device was still alive and would be powered by Windows 7. Earlier rumors had suggested that the tablet might end up sporting a version of Palm's WebOS.

The Slate 500 finally debuted in late October, targeted for the small and medium business (SMB) market. Running Windows 7 Professional, the tablet uses an 8.9-inch touch screen, compared with the iPad's 9.7-inch display. The Slate 500 includes an Intel Atom CPU, 2GB of memory, 64GB of solid-state storage space, integrated Wi-Fi and Bluetooth, and offers both front-facing and rear-facing cameras.