How can Knoppix recognize exponenets?

So my computer doesn't turn on anymore. I'm going to reinstall Windows XP Pro, but before I do, I'm using Knoppix to save all my data files. One of my login names is Ian^3. I.e. the login name has an exponent in it. When I used Knoppix it had documents and settings for Administrator and for guest, but Ian^3 wasn't there. Does Linux not recognize exponents, and if not, is there anything I can do to get around this and get those files? Thanks for any help and tips.

-Ian