Code referring to an iPhone 4S has been found in the latest beta version of iTunes 10.5. 9to5Mac reports that separate listing for black and white iPhone 4S models have been found in the beta software, along with pointers to the icons for the CDMA versions of the iPhone 4. The report suggests that while these image files may just be placeholders, it appears more likely that the iPhone 4S will sport the same external design as the CDMA iPhone 4, save for the SIM slot. Also noted in the report is the fact that only two iPhone 4S listings appear, unlike the four listings—black/white for both CDMA and GSM—for the iPhone 4, suggesting that the iPhone 4S will be a dual-mode CDMA + GSM device. Apple is expected to announce its new iPhones at a special event to be held tomorrow.