It's true. In GA you have to have a firearm in a holster when on your body. Silly law but it is what it is.
IIRC I believe that the various clips you can install on your firearm constitute a holster.
I borrowed this from a post at ar15.com
http://www.state.ga.us/services/ocode/ocgsearch.htm
"16-11-126.
(a) A person commits the offense of carrying a concealed weapon when such person knowingly has or carries about his or her person, unless in an open manner and fully exposed to view, any bludgeon, metal knuckles, firearm, knife designed for the purpose of offense and defense, or any other dangerous or deadly weapon or instrument of like character outside of his or her home or place of business, except as permitted under this Code section.
(b) Upon conviction of the offense of carrying a concealed weapon, a person shall be punished as follows:
(1) For the first offense, he or she shall be guilty of a misdemeanor; and
(2) For the second offense, and for any subsequent offense, he or she shall be guilty of a felony and, upon conviction thereof, shall be imprisoned for not less than two years and not more than five years.
(c)
This Code section shall not permit, outside of his or her home, motor vehicle, or place of business, the concealed carrying of a pistol, revolver, or concealable firearm by any person unless that person has on his or her person a valid license issued under Code Section 16-11-129 and 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."
Here's another good link:
http://www.georgiapacking.org/law.php