ugh, now to be extra careful with locking as they know your place. We bought super cheap alarms at radio shack, granted you have to activate with a key but they make a horrid shriek if you open the door when they are on. Even the dog would hear it! Of course it would freak out the cats and they already are missing their catnip 
If you see someone rolling around in the grass call the police - ha, ha
Sky King
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Gilles Berthoud "Bernard"
Surly ECR "Eazi"
Empowering the Bicycle Traveler
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