I came across this article on another site. It was something that I had no idea existed. Furthermore, how can they have illegal aliens register for the draft? Doesn't make any sense to me.

WHO MUST REGISTER - CHART Printer Friendly Version

Does every young man have to register when he turns 18? Just about!

Almost all male U.S. citizens regardless of where they live, and male immigrant aliens residing in the U.S., are required to be registered with Selective Service if they are at least 18 years old but are not yet 26 years old. Men who are 26 years old and older are too old to register. Some requirements are shown below:

Category YES NO
All male U.S. citizens born after December 31, 1959, who are 18 but not yet 26 years old, except as noted below:
X
Military-Related
Members of the Armed Forces on active duty (active duty for training does not constitute “active dutyâ€