Hi innspiral,
1. Open file "\App_Code\DNNChatProvider.vb"
2. Find section below
Return New CuteChat.AppChatIdentity(user.Username, False, ToUserId(user.Username), HttpContext.Current.Request.UserHostAddress)
3. Change section user.Username to the value you need.
For example
Return New CuteChat.AppChatIdentity(user.Email, False, ToUserId(user.Username), HttpContext.Current.Request.UserHostAddress)
Regards,