/usr/share/services/kaffeine_xine-codec_install.desktop

===========================BEGIN===================================
[Desktop Entry]
Encoding=UTF-8
Type=Service
ServiceTypes=Kaffeine/CodecInstall
X-KDE-Kaffeine-codec=ffmpeg
X-KDE-Kaffeine-engine=xine-engine
Exec=kdialog --msgbox "Hello World"
===========================END=====================================

/usr/share/servicetypes/kaffeine_codecinstall.desktop

===========================BEGIN===================================
[Desktop Entry]
Encoding=UTF-8
Type=ServiceType
X-KDE-ServiceType=Kaffeine/CodecInstall

# The unplayable codec
[PropertyDef::X-KDE-Kaffeine-codec]
Type=QString

[PropertyDef::X-KDE-Kaffeine-engine]
Type=QString

# If true, Amarok will show a warning dialog about the experimental nature of this plugin.
[PropertyDef::Exec]
Type=QString
==========================END=======================================