Citroen Xsara Picasso killed my wifes car?

Hi All,

I hope somebody can give me a bit of advise, I think I may have kiled my wifes car and if I can sort this I might get out of the dog house.

The story, I was attempting to jump start my own car (a saab) from my wifes picasso, I had attached the jump leads to the jump points under the bonnet of the Citroen and attached this up to my saab. I now know this was probably not a great idea but after leaving the car attached for about 5 mins I attempted to start the Saab with no joy. I then when to disconect the jump leads from the Citroen (without turning it of first, another mistake as I now know ,I was in a bit of a flap as late for a meeting) at this point there was a spark and the citroens engine died. I went to try the ignition and the car is now tottally dead. not a single light on the dash and no sounds made from the ignition.

I have tried a
1. a different battery
2. the same battery following a charge
3. Checked all the fuses inside and under the bonnet, all are fine.

Is there anything obviouse that could cause this that I can try? I am not too keen on calling out an auto electician as the car is only worth £200 on a good day.

Any help or advice would be greatfully recieved, even if it just that it is a lost cause.

Many thanks,

le_bonn