UPDATE value changed to 0 and other value not updated

[A Frog]

Hi everyone!

I'm trying to set up a "forgot password" script on my site. I've got a user's table with a couple of fields, including a "password" field (varchar(128)) and a "salt" field (varchar(50)). I'm trying to change the values with the following PHP Code:

$result = mysql_query("UPDATE `users` SET `password` = 'b8c25c088d0f249c4fb5fucdfd94b0e61fd939c01aa0be967078f3f5afb0170d4aae0b3131d0c87d6ca6ce7dea961661f78555c512d44ec91b5726b307181026' AND `salt` = 'T?*93q0xf6V:K]cd$IAO~*kZmikYE<.@:k@q*X1Ks_(uw+!pH@' WHERE `email` = '[e-mail]'");
if (mysql_affected_rows() == 0) {
$page->content .= 'Couldn\'t create a new password: the e-mail address doesn\'t exist in our database.';
}

In the code above I've filled in the PHP variables with example values, of course I use mysql_real_escape_string() in my real script. I always get the "couldn't create new password" error and the log shows a message about an invalid MySQL resource. When I look in my database the salt field isn't updated and still has the old value, while the password field has 1 character: "0", instead of the password.

What am I doing wrong? Why doesn't this work?

Thanks on forehand!