Have you upgraded OpenSSH to 3.7.1p2 because of the security problems, do you have sshd configured to use PAM, and now your Windows clients can't connect? Hey, what a coincidence, me too.
If you look a little closer at the dialog box that the Windows client pops up when you do a Quick Connect, you'll notice that there is a pull down menu at the bottom labeled Authentication Method. It defaults to Password. Try switching it to Keyboard Interactive and you should be able to log in.
It seems that the best fix for this is to edit the Quick Connect profile and add Keyboard Interactive to the acceptable authentication methods. Then in the Quick Connect dialog box choose <Profile Settings> for the Authentication Method. Connect and then choose Save Settings.