Take it you have found the sump drain plug then looked at the square hole in it & got stuck, Halfords sell a socket like tool that will fit & allow you to undo the sump bung, its normal for older French stuff to be odd like this, like Torx screws they where trying to stop people other then dealers servicing / repairing there own cars.
Make sure you have a new sealing washer, cheap from any Peugeot main dealer & dont go to mad tightening up the sump plug as im pretty sure the sump is alloy & you can strip the thread if your heavy handed with it.
Lee, July 2007
