On the AT&T iPhone 4S running iOS 5.1 and higher, the only data indicatoers you'll see are none, GPRS, EDGE, and 4G. It will never show 3G, even if the area is HSPA only.
It shouldn't even show 4G at all. Seeing that neither HSPA+ or LTE is 4G, but still only 3G.
The AT&T bundle the 4S' 5.1+ firmware is setup to not allow the 3G symbol to show at all. The DataIndicatorOverride is key is set to 4G and the DataExclusionOverride key is set to 3G.
Engrish?
On the AT&T iPhone 4S running iOS 5.1 and higher, the only data indicatoers you'll see are none, GPRS, EDGE, and 4G. It will never show 3G, even if the area is HSPA only.
It shouldn't even show 4G at all. Seeing that neither HSPA+ or LTE is 4G, but still only 3G.