disable volume buttons
I had this problem a LOT with my Thunderbolt. The solution I went with was to buy a low-profile TPU case for it and I've LOVED this solution. Not exactly what you're asking for but it might be something to consider. I chose a $5 "S-Line" case from eBay that lots of people sell. It's great and adds a lot of protection at little cost and is as low-profile as you can get a case to be imho.