I don't know, unless you are a professional comedian, you shouldn't be making racially tinged jokes, because one of the attributes of a joke is that it should be funny. Personally, I didn't find it funny, so to me, it just comes across as an exploitative sterotyping of a culture. But, that's just me, and it's not like I'm going to be up in arms about it.
Edit: Maybe "shouldn't" is not the right word, people are of course free to do whatever they want to do. It's going to come down to if the person finds it funny or not as to whether or not they find it offensive in most cases, which is purely subjective.