Airport problems

I'm travelling tomorrow to Djerba and I'm planning to take my underwater case for my NEX 5 with me. Do you think I'll have problems if I take it on my hand luggage instead of putting it at the airplane cargo inside my big suitcase. The underwater case is the cheap/amazing Meike. Here: http://www.youtube.com/watch?v=vpZl1XczR0U

The security may think that if I broke the case during flight, I could satab someone with the resulting sharp pieces !!! What do you think? Cargo or hand luggage?

Thanks
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Miguel Teotónio