Apple has released a third beta version of its iPhone software developers kit (SDK) that suggests a change in chips that may confirm a 3G iPhone will be with us this summer.

The new iPhone SDK sports clues that the next version of the popular device will include Infineon Technologies AG's S-GOLD3 chipset, according to information posted by the makers of ZiPhone, an iPhone unlocking utility.

In a screenshot posted to the ZiPhone website, the S-GOLD3 chipset is called out in the newest version of the iPhone firmware, which shipped with the revised SDK beta. "Well this was found inside the latest beta," wrote one of the ZiPhone creators, identified as 'Zibri'.

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According to documentation (download PDF) on the Infineon website, the S-GOLD3 chipset includes an EDGE-capable modem, as does the older S-GOLD2 Infineon chipset that researchers and users have spotted in the current iPhone.

But unlike the S-GOLD2, the newer chipset can be partnered with other chips, notably WCDMA co-processors, to enable access to faster 3G-based data networks. "[The] S-GOLD3 is configurable with a number of co-devices such as multimedia companion chips and/or WCDMA co-modem for 3G feature phones," Infineon said in a two-page datasheet for the S-GOLD3.

If included in a revamped iPhone, the S-GOLD3 chipset could also beef up the resolution of the phone's camera and possibly handle video calling. "Even the most performance-greedy applications such as video telephony and 3D graphics can easily be handled without additional hardware," bragged Infineon in its materials.

The data sheet also noted that the chipset's camera interface is capable of handling up to 5Mp; the current iPhone's camera maxes out at 2Mp.

Infineon also makes and sells a close cousin to the S-GOLD2, dubbed S-GOLD3H, that is an all-in-one 3G-capable chipset. Some websites and blogs, including numerous Apple-centric sites, such as AppleInsider, which first reported on the ZiPhone finding, have touted the firmware's 'SGOLD3' reference as referring to the even faster 'H' model.

Technology and financial analysts who cover Apple have been predicting that the company will introduce a 3G-capable iPhone this summer - most likely in June or July - as it wraps up work on its iPhone 2.0 firmware, which CEO Steve Jobs announced early last month.

Last week, analysts said rumours that Apple has placed large orders for 3G iPhones with its Asian manufacturers are probably correct. "A 10 million order for 3G iPhones for delivery over the remainder of the year makes perfect sense," Ezra Gottheil, an analyst with Technology Business Research, said last week.

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