My advice to you: "Think about what you would have told a white man"
Well that leads to something like "Toughen Up, It's Part of the Job".
I don't think it helps to activly missunderstand people, when they are trying to be helpful EVEN if their trying is in the wrong. Try to think about the intention and maybe ask what they really meant by that.
I hope we can all agree that in 90% of the cases we can hear on the tone in the voice what the poster meant. If unclear ask and if racism occurs report the ** out of him :D