95mtlMAXSE

I was checking around on old threads and figured out how to program my remote and all. It went great, but i want to know, is it possible to program the 2003 type keless remotes to our 4th gen's? If so, how can I program it(it didn't work I have 2 of them). If not well, i guess i'll live with it, but i really like the newer ones and would really like for them to work.
Thanks in advance
ed