Here's what I found:
According to the State of Virginia's Dept of Alcoholic Beverage Control,
http://www.abc.state.va.us/licensing/abcfaq1.htm
Q: How old does a waiter or waitress have to be?
A: Waiter or waitress - 18 years of age, Bartender - 21 years of age.
Q: What type of clothes can be worn in the restaurant by employees?
A: Basically, any type clothing may be worn provided it has not been provided
by a wholesaler. However, on the premises of a mixed beverage licensee
clothing which stresses nudity or near nudity is prohibited.