San Francisco  - Apple's eagerly awaited new iPhone went on sale around the world Friday but software glitches that hampered the activation of the new devices caused lengthy delays and left many buyers frustrated.

The problems were traced to Apple's iTunes store where users' account information is held.

"There's a worldwide issue with iTunes that Apple is working to resolve," an AT&T representative said. "We have had reports that customers attempting to download new iTunes 7.7 software to their new iPhone may get an error message saying 'page not found.' We have reported this issue to Apple. While Apple works to resolve this issue, we are asking customers to sync their newly activated phone later at home."

Lines in New York, San Francisco and elsewhere in the US had generally been shorter than those seen a year ago when the original iPhone was launched. But problems in activating the new devices meant that lines grew longer by the minute. That didn't faze the Apple faithful however, many of who had camped out overnight to get their hands on the new gadget.

"I could get someone to do this for me," said Apple co-founder Steve Wozniak, who waited in line from 4 am onwards outside an Apple store in Silicon Valley. "But, it's fun. We are all here - Macintosh enthusiasts."

Stores in some 20 countries opened their doors at 8am local time on July 11 to sell the communications device which combines an advanced phone, with email and internet access, a GPS locator and an iPod media player. Lines were reported in Australia, New Zealand, Japan and across cities in the US.

The iPhone 3G is hitting stores a year after the launch of the original iPhone sparked a wave of hysteria among gadget junkies and announced Apple as a major player in the market for smartphones previously ruled by Nokia, the Rim Blackbery, Samsung and LG.

Apple has sold an estimated 6 million of the original iPhones before running out in May. In the US, an 8-gigabyte model is selling for 199 dollars, or a 16-gigabyte version for 299 dollars from Apple or AT&T, the exclusive US wireless partner. The phone comes in black or white and requires the activation of a two-year service contract with a minimum monthly charge of 70 dollars a month.

The main upgrade in the new phones is that they run on so-called 3G networks which are much faster for data download and internet surfing than its predecessor. It also features a GPS location device.

However, the battery life has also been compromised by use of the 3G network and often requires daily recharging.

Reviews have generally been positive but less enthusiastic than those which greeted the original iPhone.

"If you've been waiting to buy an iPhone until it dropped in price, or ran on faster cell networks, you might want to take the plunge, if you can live with the higher service costs and the weaker battery life," said Walt Mossberg of the Wall Street Journal, the doyen of gadget reviewers.

But he advised people who already own an iPhone who can use Wi-Fi for data to wait and get the free software upgrade before thinking about a new phone. (dpa)