I had the same problem a few minutes ago.
I wasn't able to install the extra protocols for Conversations.

I just deactivated the Extras-Devel repository and tried again to install it. Then it works fine.

Don't search for the upstart job. You won't find it.

With deactivating the Extras-Devel, the App-Installer is showing "older versions" of software, so you can install it.