Password-Protected Galleries

Is there a way to have multiple password-protected galleries with simply the password directing you to the correct album?

I know how to password-protect a page, but I don’t know how to make one password box that, depending on which password is entered, will take you to that particular page.

Here is an example: http://www.christinechilds.com/proofing.php?ProofingButtonName=Client%20Proofing

Please help!