tracking what users do in a data base

I have a problem and wonder if anybody has ran across this .

I developed a reservation system for a small hotel
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there are five user and all but one user has no problems making reservations etc... One user always has a problem with the system , either it don't work for him or he says he puts reservation in the system but they never show up. even asked him to show me how he makes reservations and it works for him when he shows me. i know he is just being lazy or for some other reason trying to make the system not work so we can go back to hand writing them.

here is want i want to do and sort of have a idea but need other thoughts.

i want to track with out everyone knowing it who hits what buttons and what scripts they use and if they somehow abort the script...

it really throws a wrench in the works because it make it seem the system i wrote is not working right. i need to track what layouts he brings up etc etc