Thanks for your bugreport. I can't find a gnome-hideseek package in ubuntu. I'm sorry but this seems to be not a apt bug, but a problem with the package. About the keys warning, this is expected behavior. Either add them with apt-key or not mix debian and ubuntu sources in your sources.list.
Cheers, Michael ** Changed in: apt (Ubuntu) Status: Unconfirmed => Rejected -- Package installers or locked up https://launchpad.net/bugs/71739 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs