Is it realy possible to marry by internet(chat)?

A girl used to talk to a guy on net(chat).They became net friend. One day the guy said I take you as my wife and I want you to say kabol-hai kabol-hai kabol-hai.She thought he was kidding so she said kabol-hai kabol-hai kabol-hai. But then the guy just changed and said four people are sitting near to me who saw this chat and I will save this conversation as a proof that you accept me as your husband.Now the girl is worried as she hasn't said it in words besides no one was there with her,she just typed also he didn't tell her of his intentions before asking her to say kabol-hai.So by the islamic regulations are they married or is he just bluffing. (all this happend only by type)