HOWEVER, upper-stages to move satellites to GTO are ejected out of earth orbit (for safety reasons - you don't want it to add to the space junk problem). These ejected stages are taken through an Earth-Moon Lagrange point, before being navigated on a low-energy path to a heliocentric orbit. There's no reason a microsat can't hitch a ride on an upper stage, and then wait until the ejected stage reaches the L-point before deploying itself, at which point it's downhill to anywhere in cislunar space.

People are currently working on doing this: http://www.lunarcubes.com/