I am using Linux Mint 15 RC Mate (up to date) on a PC with an AMD64 CPU.
I uninstalled sbackup (Simple Backup) using the Software Manager and later reinstalled it. Although the installation seemed to proceed normally, when I tried to start the program from the applications list, it was listed four times, but could start. Right-clicking did not offer the option of removing three instances from the list. Uninstallation got rid of all four.
To get rid of this nuisance, I uninstalled and reinstalled it using the Package Manager. Again when I try to start it it comes up four times.
Why do you think this is a PackageKit issue? I think sbackup probably installs multiple desktop files or the menu generation code is buggy.
I had no idea what kind of issue it was. I was merely reporting what I did to bring on the bug.
We moved the upstream bugtracker to GitHub a long time ago. If this issue still affects you please re-create the issue here: https://github.com/hughsie/PackageKit/issues
Sorry for the impersonal message, and fingers crossed your issue no longer happens. Thanks.