can't install ros-electric-ros-full

edit

I was having an issue where I upgraded something, which caused ros-electric-geometry to get removed. I went to reinstall it with apt-get, and it wouldn't install (said it depended on something that wasn't going to be installed), so I removed ALL of my ROS stuff (purge, autoremove, update). Now when I try to install ros-full, I get:

The following packages have unmet dependencies:
 ros-electric-ros-full : Depends: ros-electric-rx (= 1.6.1-s1323597255~natty) but it is not going to be installed
                         Depends: ros-electric-ros-comm (= 1.6.6-s1323590699~natty) but it is not going to be installed
                         Depends: ros-electric-documentation (= 1.4.3-s1323617999~natty) but it is not going to be installed

If I follow the chain of unmet dependences through, I eventually get here:

$ sudo apt-get install krb5-multidev
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help resolve the situation:

The following packages have unmet dependencies:
 krb5-multidev : Depends: libkrb5-3 (= 1.8.3+dfsg-5ubuntu2) but 1.8.3+dfsg-5ubuntu2.1 is to be installed
                 Depends: libk5crypto3 (= 1.8.3+dfsg-5ubuntu2) but 1.8.3+dfsg-5ubuntu2.1 is to be installed
                 Depends: libgssapi-krb5-2 (= 1.8.3+dfsg-5ubuntu2) but 1.8.3+dfsg-5ubuntu2.1 is to be installed

I've seen problems like this before, but haven't had luck with any of the solutions out there. Any ideas?