To program additional remotes, theres a procedure to program on the car or you have to bring to a GM-Service ? :?

I found this on another site. It still might work although it appears you still might need the dealer'* help:

1996-1998 Bonneville

ALL TRANSMITTERS MUST BE PRESENT WHEN PROGRAMMING NEW REMOTES!

1) Turn OFF ignition switch
2) Use a 3 amp fused jumper wire and connecte the terminal 8 (blk/wt) and terminal 4 (blk) wires at the data link connector. The data link connector is located on the drivers side bottom of dash panel
3) Close all the doors
4) Turn ON the ignition switch. The locks will cycle to LOCK
5) Press and hold LOCK and UNLOCK on one of the transmitters for 30 seconds.
6) After a 30 second delay the doors will LOCK and UNLOCK.
DO NOT TURN OFF THE IGNITION!
7) Repeat step 5 for each additional transmitter
Disconnect jumper wire from data link connector. Then turn ignition off and verify functions.

eBay is a good source for a replacement transmitter, but understand that they are NOT interchangeable. You must use the ONE that is meant for your car.

But this works on a 2004 model?

Well, it says 1996-1998 Bonneville but maybe worth a try?

not if it shorts the pcm and other components cause the datalink pins may have changed since 98.

Well, that'* what the warranty is for. Besides, the inline fuse will catch any shorts.
Not saying you should intentionally screw up your car, but if you do cause a short circuit I would button everything up, say nothing about what you did and call the dealer for a repair. Either that, or you're gonna have to pay to have it done. That'* the reason GM doesn't make certain info such as pinouts and fob codes public information.

No, the warranty is for problems that are generated in the manufacturing process. They are not for the clueless that decide to poke into things thay have no understanding of the function. Just because you don't have to pay for your screw-ups doesn't mean they are free. Manufacturers pass on all costs to their customers. What is GM losing? One Billion a quarter?

Well, in that case, who are you to modify anything in the vehicle that is not specific design from GM engineering? That includes oil, filters, cleaning solvents etc. I would imagine that your vehicle is 100% OEM, otherwise your warranty claim could also be considered fraudulent. People who live in glass houses........

The Moss-Magnuson act says the dealer has to "prove" that the oil filter I am using caused the problem. If they do then it'* between me and the filter manufacturer. On the other hand, who is responsible when someone starts shorting wires that they have no idea as to what they run? My point is that you are giving bad advice on a good forum and hiding behind the manufacturers wallet while doing it. Your response tells me you understand my point.

My dealer told me you can have up to 4 of them and yes you have to have a dealer do it! Sorry I hate how for every lil thing the dealer is the answer!