you are wrong pieter

....if u just disable/delete the job without restarting/closing the service manager the job is still active until you restart your computer!
i know this because i had the same problem even thou i had deleted the job itself
EDIT: every time you make a change in sql jobs you need to restart "sql service manager" (rightclick the sql icon next to the clock and choose "sql service manager") and then u can restart that one..
Not 100% sure about that its named "sql service manager" because i dont have a active server atm so i can check, but its named something like that..