Version 1.7.5 of Jettison is now available. It ensures that encrypted sparsebundle disk images are locked after being ejected, so if you’re using them as “secure containers”, they’ll be safely locked when your Mac goes to sleep. Getting at the files on them after waking the machine will require you to re-enter the secure disk image’s password.
In addition, this release of Jettison corrects several bugs that could cause it to hang, or that caused its icon to disappear from the menu bar even when it was still running. It also lets you use function keys as keyboard shortcuts without combining them with a modifier key.
Full details and download links are available on the Jettison Release page.