GnuPG passphrase cached until logout on 12.10

I have been GPG signing my e-mails with the Enigmail add-on for Thunderbird for some time now. Whenever I do, I get the following window:
http://i.imgur.com/fgZAi.png

Recently, I started trying 12.10. When I attempt to sign an e-mail for the first time after I log in, I get the following window:
http://i.imgur.com/oUg0Q.png

Notice the absence of the options. After I enter my passphrase, Ubuntu remembers it until I log out. How do I get those options back?

UPDATE: I've also raised the issue here and here.