I really hope someone could help me out with this...I have an SQL database for my server that contains usernames and passwords for all my clients. When people create their accounts on my website (CMS), their passwords are encrypted in SHA-1 Hash form...

Now, I'm making a program that requires authentication. So basically the person is supposed to enter their information (username and password) that is stored in the SQL database to be able to access the program. I am using THIS tutorial to teach me how to do this: http://www.youtube.com/watch?v=u1waZnO8PCk

One problem, since the passwords are stored in SHA-1 I can't think of a way to make it read the SHA-1 passwords that are stored in the DB, when the person enters a string type piece of text as their password while they try to login.

Could anyone help me out? Thanks