developing plugins - newbie help needed

[Molle Bestefich]

I am trying to learn how kdeaddons/konq-plugins/arkplugin works.
Going relatively well, I can build and install it, but the plugin is
never loaded in Konqueror.

Right-clicking a .tar.gz file (for example) doesn't yield any extra
menu items, neither does clicking compressible items.

I'm wondering how KDE loads it's plugins, and why mine isn't loaded.
There's no logfile I can look at, and no place to enable/disable these
things from kcontrol, it seems.

Clues?
How does Konqueror decide which plugins to load?
When does the loading occur (do I have to restart KDE?)?

This is what "make install" in my project does:
  (install docs)
  mkinstalldirs /usr/kde/3.5/lib/kde3
  libtool --silent --mode=install install -c -p libtestproj.la
/usr/kde/3.5/lib/kde3/libtestproj.la
  ldconfig -n /usr/kde/3.5/lib/kde3
  (install icons)

ls -l /usr/kde/3.5/lib/kde3/libtest* shows that a .so file was also
installed, though it's not described by the output of "make install".

No extra menu items :-/.