Comment 3 for bug 56749

looks like you installed libgnomevfs2-common from dapper-updates and not have that source in your sources.list at the moment which makes it impossible to grab the corresponding libgnomevfs2-extra, you might want to get it from the same place you used for libgnomevfs2-common. Closing since that's not a bug. Feel free to reopen if you still have the issue when using dapper-updates source too