Movie where cat turns into a human?

I remember this movie that I got from a rental place. It was about this boy, who loved his cat, and he went to the museum or something and an Egyptian artifact turned the cat into a human. He then started to look for his cat's birthplace or something and the cat thought it was at Oxford. I thought for sure it was called Mr. Whiskers but now I'm not certain. It might have been a disney movie. I really can't remember that much about it, but I loved it.