Escamillo,
I had a similar experience with a kitchen cabinet which would not remain shut. My apartment has high ceilings. The cabinet in question was at the very top, latched every night and opened every morning. It was strange since I had to get on a ladder to latch it. One night about 3AM I heard a noise in the kitchen and found that my cat was jumping from the counter top to the cabinet handle - an 8' jump - and hitting the handle until the door opened. Then he went in and slept. Mystery solved.