I would assume that this would be okay, actually. After all, you have full access to do as you please, you pay for space and your webserver has it's own IP address (I assume, most do...) than this should be no problem. If you don't have your own IP, or for some reason it is shared with others than I wouldn't do this. But I cannot for the life of me think of any reason this would be the case. People set up hacking training on websites they don't host and it isn't illegal. I guess it depends on your country/specific laws though.
All in all, I would be completely confortable doing this with my own setup here in the U.S.A. I forsee no issues with this.