Try to install them by hand do sudo apt-get install cpp cpp-4.0 than try to sudo apt-get dist-upgrade. If the problem still persists best thing to do is change your sourceslist file back to breezy than make sure breezy is uptodate than change the list back to dapper and sudo apt-get update && sudo apt-get dist-upgrade.
-- upgrade to 6.06 fails https://launchpad.net/bugs/53714 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
