about to get crazy, help

[MrPolite]

I have this:

// Make sure the value is at least 0
if (intensityCount[curIntensity]<0) intensityCount[curIntensity]=0;
// Add one
intensityCount[curIntensity]++;

// Sometimes the debugger stops here!!!!
if(intensityCount[curIntensity]==0) System.Diagnostics.Debugger.Break(); 

and here's how the array is declared:
byte[] intensityCount= new byte[255];


I don't understand what MIGHT be possibly wrong. I'm assuring the element of the array has a value of at least zero. Then adding 1 to it, and it's still ZERO?!!!! what the heck?? any ideas?