note 40100 added to function.sha1

I just wanted to add a comment SHA1 being surjective and that it shouldn't be used to make unique IDs. This is true. Note however that for a hash function to be good (and SHA1 is deemed pretty good), it should be collision resistant, meaning that it is awfully hard to come up with 2 messages that hash to the same value. Cheers. ---- Manual Page -- http://www.php.net/manual/en/function.sha1.php Edit -- http://master.php.net/manage/user-notes.php?action=edit+40100 Delete -- http://master.php.net/manage/user-notes.php?action=delete+40100&report=yes Reject -- http://master.php.net/manage/user-notes.php?action=reject+40100&report=yes Search -- http://master.php.net/manage/user-notes.php