IPhone fans may be experiencing déjà vu when trying to activate the newly released iPhone 3G S, as Apple is struggling to handle the demand from hundreds of thousands of users.

"Your activation requires additional time to complete," reads a message from iTunes for some iPhone 3G S customers. "Due to the current volumes, it may take up to 48 hours to resolve your issue."

Apple has not responded to press inquiries regarding the delays, and it's unclear how many customers this is affecting. The issue appears to mirror problems Apple had with the release of the iPhone 3G last year, when the company's servers could not cope with the demand.

The company did take multiple steps to try to prevent activation issues, though, as Apple rolled out the new iPhone 3G, the 2.0 software, and the MobileMe service at the same time last year. The company took a staggered approach this time, releasing the 3.0 software a few days before the new hardware was released. Apple also likely took steps with its server architecture to handle the demand as well.

While the problems are likely to frustrate some iPhone 3G S owners, the delays and activation issues do not seem as bad as last year where iTunes' woes led to long lines at the point of sale. Blogger Eric Zeman purchased a new iPhone on Friday morning and said the experience was "much faster than 2008, by a long shot," although he did preorder his device.

Kevin Mobley, a software performance expert at The Ian Thomas Group, said continual activation issues are eventually going to hurt Apple's brand. He suggests the company build a workload profile of users, and potentially block out activation times for customers depending on their region.

"Going forward, as Apple presumably gets deals with other carriers and grows the iPhone user base, they'll have to determine if iTunes is really the best solution for activation," said Mobley.

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