Thanks guys. I went into the Baby Factory on our walk this afternoon and asked about them. The lady didn't know too much though!
I ended up buying a couple of packs of the rubbery plastic strip thingys

which I can use to strap the drawers closed. Make sense??!
Will try them out tonight, and then let Nate loose tomorrow to see if they are monster-proof.
I'm too scared to leave them unsecured as the drawers are all pretty big and are full of serving plates etc, so heavy. Recipe for disaster with my child who just will not stay still!