[Digikam-users] Problems upgrading DigiKam on Linux Mint

[Kim]

I'm running Linux Mint 17.1 (cinnamon), it has DigiKam 4.0.0 but I've 
found it to be very unstable on my laptop and I'm trying to upgrade to a 
newer version.  I have Philip's ppa installed both kubunto backports and 
extras, however it still wont let me install anything newer then version 
4.  Looking at the ppa version 4.7 should be available.
Has anyone had this problem with Mint?  When I'm in the synaptic it 
doesn't show that a DigiKam upgrade is available and if I uninstall the 
current version and refresh it still only gives me version 4.0 as an 
option.
Any ideas how to get an upgraded version?

Thanks,
Kim