Some Apple Inc. customers who bought the company's AirPort Extreme router are angry that the new Time Capsule backup appliance introduced last week leaves them on the short end of the backup stick, according to messages posted on Apple's support forums.

Their problem with AirPort Extreme and its AirPort Disk feature, which lets users attach an external Universal Serial Bus drive to the router and access that disk via the wireless network, goes back to late October 2007, when Apple launched Mac OS X 10.5. Although Apple had said earlier in the year that Leopard's backup application, dubbed Time Machine, would work with AirPort drives, the feature was yanked before the operating system finalized.

In a note posted to its site on Oct 26, the day Leopard launched, Apple acknowledged that Time Machine didn't support AirPort drives, but it did not give an explanation.

As soon as the company unveiled Time Capsule, hardware that integrates a wireless base station with a 500GB or 1TB disk drive, people who had bought the AirPort Extreme began complaining.

"I was one of the suckers to buy an [AirPort Extreme] and 500GB hard drive when Apple posted that Leopard would be the answer to the backup problem," said a user identified as John Wolcott. "All you needed was [AirPort Extreme] and USB drive, and Time Machine would do the rest. I believed them, and look where that got me."

Another user with the alias "speakerfritz" chimed in: "I went out and bought three [AirPort] Extreme base stations to use the printer and drive features and the Time Machine backup feature [that was] initially stated extreme would support. And like many ... we all found out that Time Machine won't work on an Extreme unless you rig it to do so, and even then it does a poor job.

"I feel like I [have] been had."

Other messages came from users who said they hope Apple would update the AirPort Extreme to add Time Machine support, while still others criticized Apple for deleting posts from the support forums.

"This Time Capsule thing is just adding insult to injury," argued Christopher Chang. "Please Apple, update Leopard and the AEBS [AirPort Extreme Base Station] firmware so I can do wireless backups with my MBP and AEBS. For the love of God."

"They really should be keeping us informed of their plans. Some reassurance that it will be fixed, and some approximate time scale would make a huge difference. It's all very well [that] the moderators [are] deleting posts with rants and speculation, but if Apple did a better job of responding to issues like this, then there wouldn't be so many rants or speculation," said a user tagged as "bilbo_baggins."

Apple, however, has been mum on the subject. In his keynote last Tuesday, CEO Steve Jobs said nothing of an update for existing AirPort Extreme owners, although he cited updates for other products, including a US$20 upgrade for the iPod touch and a free update for AppleTV. Apple also did not respond to a series of questions last Friday about whether an update would be provided, and if so, when.

Time Capsule, which comes in a 500GB configuration for US$299 and a 1TB model for US$499, won't ship until sometime next month, Apple said last week. Amazon.com, which is now taking preorders for the appliance, lists its availability date as Feb. 1.