The Californian company released its first scheduled software update for the iPhone last week, ostensibly to improve the phone's functionality to download music over a wireless network. But owners of modified iPhones who availed of the firmware update suddenly found their prized (and expensive) devices had now become an 'iBrick' . . . useless except for wedging open a door.

The touch-screen phone/personal computer hybrids, which cost $599 on launch earlier this year, have not been released in Europe yet, although are scheduled to hit the shelves in Britain, France and Germany in the coming weeks. It is expected the iPhone will be released in Ireland early next year but this has not stopped Irish people going to the US to purchase the must-have gadget and 'cracking' it to make it work on domestic networks.

Waterford-based Jason Madigan bought an iPhone from the US three months ago and hacked it to make it work on O2 Ireland's network.

"I personally won't be rushing to update this software, and I knew the risks involved when I decided to buy it to work here in Ireland, " said the telecoms engineer who added that anyone thinking of buying an iPhone now should check that Apple software update 1.1.1 has not already been preinstalled, otherwise it will not work on any Irish network regardless of alterations made.

South African Paul Watson also lives in Waterford and uses an unlocked iPhone.

He said he "wouldn't go near" any Apple updates and is unconcerned that the manufacturer will pursue his cracked iPhone through other means.

"Tracking down customers who have unlocked the iPhone would break loads of laws, particularly here in Europe, " he said.

Madigan inserted a small device called a turboSIM into his iPhone which fools the device into thinking it is running on the approved AT&T network in America rather than O2 Ireland. Less fidgety software hacks have also recently become available, including one from Belfastregistered UniquePhones that does not require any hardware.

Another software hack from iphonesimfree. com purports to work regardless of the latest clampdown from Apple and a statement on the website claims the new update, which transforms legally unlocked iPhones into 'iBricks', is a blow to the thousands of open-source programmers who have put "tens of thousands of manhours" into developing applications for the iPhone.

These applications will now no longer work on iPhones which have the new update installed and it remains to be seen what will be the reputational damage for Apple among its usually loyal customer base.