Almost a year after Apple began investigating a design fault in the 15-inch PowerBook that apparently caused white spots to appear on its screen, the company has announced an extension to the associated repair program.

The 15-inch PowerBook G4 Repair Extension Program is a worldwide program covering replacement of LCDs that exhibit "faint white spots to appear on the screen over time".

The program covers 15-inch PowerBooks that were manufactured from July 2003 to November 2003 and fall within the following serial number ranges: V7334xxxxxx to V7345xxxxxx and QT331xxxxxx to QT339xxxxxx. This range encompasses Aluminum as well as Titanium PowerBooks.

Apple offers advice for people wishing to check if their PowerBook displays the white spots. This involves changing the desktop display colour to light grey.

Seeing spots

Last November Apple issued a statement saying: "The new 15-inch PowerBook has been a big hit with customers since its introduction last month. However, some customers are reporting the appearance of faint white spots on their displays after using the system for a short period of time, and Apple is investigating these reports right now. Any customers experiencing this problem should contact AppleCare."

At the time many PowerBook users posted details of the glitch on Apple's forum. One PowerBook owner said: "On my PowerBook screen there seems to be a spot where things appear brighter than the rest of the screen. It is about one-inch in diameter. It almost looks like the white spots that occur when you push on the back of the screen. The computer is brand new, and it has had the spot since I bought it."