2001 Other Suzuki Models will not start

Having just changed the battery on my wifes suzuki ignis, i could not get the car to start, i called out the AA who have said that the imobilizer is staying on. this is because the battery that i took off was flat and the imobolizer has kicked in ! I have the owners manual and it gives me the key code. the AA guy is saying that it,s a main dealer job, but i sure you don,t have to run to the main dealer every time you change or disconnect the battery. Can anyone explaine have to re-programme the key or any other short cuts.

Thanks

Steve.