Did you try updating the lists and then installing again? Maybe it was a hiccup on the mirror. Apart from that, your sources.list is not 'complete' - you can try:
deb http://us.archive.ubuntu.com/ubuntu dapper main restricted universe multiverse deb-src http://us.archive.ubuntu.com/ubuntu dapper main restricted universe multiverse deb-src http://us.archive.ubuntu.com/ubuntu dapper-updates main restricted universe multiverse deb-src http://us.archive.ubuntu.com/ubuntu dapper-updates main restricted universe multiverse deb http://security.ubuntu.com/ubuntu dapper-security main restricted universe multiverse deb-src http://security.ubuntu.com/ubuntu dapper-security main restricted universe multiverse deb http://packages.freecontrib.org/ubuntu/plf/ dapper free non-free It's definitely not a bug as you can see here: https://launchpad.net/distros/ubuntu/dapper/+source/gtkmm2.4 all versions built, on all architectures. Try opening a support request (http://launchpad.net/support). Look for held packages, try apt-get install -f ** Changed in: gtkmm2.4 (Ubuntu) Status: Needs Info => Rejected -- Dependency problem installing libgtkmm-2.4-dev https://launchpad.net/bugs/54289 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs