Possible Duplicate:
Fixing Broken Packages

I am trying to install the nautilus-actions-extra package via synaptic. When I do synaptic advises me that I have broken packages.

I have followed How do I locate and remove Broken Packages that I have installed? but when I select the Status category, I do not have a 'Broken Dependencies' option.

When I click on the 'Broken' item in the Filter category nothing is displayed. I am using Ubuntu 12.04LTS. What can I do to resolve this?

These are my terminal responses:

$ sudo apt-get install nautilus-actions-extra
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 to resolve the situation:

The following packages have unmet dependencies.
 nautilus-actions-extra : Depends: nautilus-gksu but it is not installable
E: Unable to correct problems, you have held broken packages.
$ sudo apt-get check
Reading package lists... Done
Building dependency tree       
Reading state information... Done