Software compatibility problems marred the launch of the iPhone 3G at Apple's flagship store in London, where customers had difficulty activating their new phones.

O2's web-based activation system requires the use of Microsoft's Internet Explorer browser to register a new phone: it won't work with the Safari browser bundled in Apple's Mac OS X.

In its Regent Street store, Apple had installed VMware Fusion desktop virtualisation software on some of its Mac computers, allowing them to run Internet Explorer on Windows, but the activation process was still not working.

"It just goes dead," said would-be customer Mark Phipps, who left the store frustrated and without an iPhone 3G.

"They wouldn't reserve us one, which is a real kick in the teeth," he said.

Phipps is one of at least three customers that left the store disappointed by the delays.

Another, Josh Young, said the activation process was completely broken. He planned to return later.

The short line that had formed outside the store by the time it opened at 8am quickly moved inside, but two hours later the line had lengthened and extended out on to the street again.

Further details were hard to come by: store staff would not allow journalists inside the building.

Macworld is also reporting massive system crashes at UK carrier O2's activation efforts, suspending many credit checks and activation orders.

The launch went more smoothly in Japan, where the iPhone went on sale for the first time. The first new iPhone owner emerged from the store of Apple's local partner, Softbank, within 20 minutes of the launch.

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