FP - is that true? It was my understanding that was rescinded a while back. *****
the pistol, revolver, or firearm may only be carried in a shoulder holster, waist belt holster, any other holster, hipgrip, or any other similar device, in which event the weapon may be concealed by the person´s clothing, or a handbag, purse, attache case, briefcase, or other closed container. Carrying on the person in a concealed manner other than as provided in this subsection shall not be permitted and shall be a violation of this Code section.
An ankle holster would seem to be covered under "any other holster".
In the 1970s when I was working in the Atlanta area, we were informed that ankle holsters were for cops only. I had previously sometimes so carried my S&W M49 bodyguard, but switched over to a Bianchi upside-down underarm shoulder rig easily enough, and modified the ankle rig for my S&W to serve as a 4-magazine carrier for my M1911A1 instead, an arrangement I've come to prefer that also saves buying ankle weights for wear while jogging.
The law could well have changed since then, or its interpretation, which could also vary in some areas.