They didn't in 1979, but when it was passed in 1980 men older than 18 had to register. Wikipedia (yes, I know, distrust all things wiki):
Then on July 2, 1980, President Jimmy Carter signed Proclamation 4771, Registration Under the Military Selective Service Act, retroactively re-establishing the Selective Service registration requirement for all 18-26 year old male citizens born on or after January 1, 1960. Only men born between March 29, 1957, and December 31, 1959, were completely exempt from Selective Service registration.[2] The first registrations after Proclamation 4771 took place on Monday, July 21, 1980, for those men born in January, February and March 1960 at U.S. Post Offices. Tuesdays, Wednesdays and Thursdays were reserved for men born in the later quarters of the year, and registration for men born in 1961 began the following week [3].
So he would have had to register in July or August 1980.
Thx for the info, i knew it was something like that but could not remember the timetable. now the question is: did he register? how old is he anyways? shows how much i care about him huh...lol...