WebApp Password Management - Hashing, Salting, etc
Your proposed solution does not really solve the problem. The server has to know the password nevertheless, so it had to be transferred at some point in plain, which was what you wanted to avoid in the first place. This way you only avoid the password being sent again every time, but if someone caught it the first time it was transferred?
I think you should not reinvent the wheel :-) Use SSL for all connections and then your first solutions works fine. You can even perform the hashing on client side, so only the hash is sent over the secure channel. Your server will never know the password, and it doesn't have to.