Handheld PC's are in such demand that manufacturers are having trouble keeping up. The crisis is such that second hand versions of handheld's from Casio, Compaq and HP have reportedly been changing hands on e-Bay for as much as £200 above the retail price.

This comes in the same week as the company launches a new drive to expand its presence in the wireless hardware market space, announcing its intentions to be a serious competitor to Palm, the market leader. Announcements of new products under the iPaq brand, including an MP3 player, are expected this week.

He said that the product had been delayed by a shortage of the screens, but that it would take a couple of weeks to ramp up production on all the components. He predicted a better situation by September, but suggested that customers put their names down for an iPaq now, or risk losing their place in the queue.

A spokeswoman for Casio said that the company was not having any distribution difficulties. No one at Hewlett Packard could be reached for comment. ®