I found some information on http://wiki.answers.com/Q/How_to_fix_the_lock_of_a_Peugeot_205
I tried this and after two hours managed to get the door open.
But after working perfectly for about 5 times it locked itself again.
It was too dark by then to see what is going on. It gave me a chance to strip the door and tomorrow after work I will have a look
again to see what is going on when I have more light.
Theo Bagchus
January 2008