In "System Settings" > "About Me" I've changed my personal image but the image I've choosen it's ignored by KDM. I'm currently using KDE 4.9.2 Reproducible: Always
KDM is unmaintained and not used in KDE Plasma 5. SDDM is the login manager used in KDE Plasma 5. If you still have this same issue with SDDM, please file an issue on the SDDM bugtracker (after doing a search for existing issues first!): https://github.com/sddm/sddm/issues/