yeah i saw your post a while back...
A bootloader is programmed to the chip using a standard programmer, the bootloader then runs on the PIC and allows new code to be loaded without a full programmer.
however none of our codes are set up to be used with a bootloader and it would be very dificult to do as the 12f683 does not have self writeable program memory.
if your uncle sent you chips with a bootloader on and you programmed that chip with a different hex file using a normal programmer then the bootloader is lost although your uncle may be able to send you the hex for the bootloader.
also there is a more limiting way of reprogramming a rf code without a bootloader like hazers final rf did, noone has done an opensource version yet, but i will be working on it in the summer.