A Brazilian company is claiming to be the first to have found a way to unlock Apple's new iPhone 3G, getting around restrictions that require users to sign up for calling plans with exclusive carriers, reports said Tuesday.

The website of Brazilian newspaper Folha de Sao Paulo and various online sites including Digg.com and Gizmodo.com said the firm, DesbloqueioBr, hacked the phone by altering its firmware and by adding a special card add-on to the SIM chip.

The results allow iPhone users to connect to any carrier, not just the one that has an exclusive arrangement with Apple in each country where the phones are sold.

In Brazil, where the slick handsets have already become a must-have item for the wealthy, the iPhone is not yet officially available.

Brazilian purchasers have to go abroad or order by the Internet to get one of the gadgets, more than one million of which have been sold since going on sale in 21 countries last Friday.

The Brazilian hack doesn't come cheap, however.

DesbloqueioBr plans to charge between 250 and 375 dollars to unlock an iPhone, which itself costs around 200 dollars in its basic eight-gigabyte version -- but only with the subsidy offered by signing on to the exclusive carrier.

There are some problems with the Brazilian fix.

One of the company's partners, Breno MacMasi, admitted that the quality of the connection for the phone can vary, Folha Online reported.

Apple can also wipe out the hack with a software update.

But MacMasi predicted that there would always be ways to circumvent the locks.

"Apple has made some big mistakes, so it's certain that we will be able to come up with another hack. It's going to be a game of cat-and-mouse," he said.