baptista,
What version of KDEPIM/PI are you using? I've found that whenever I install these programs I need to reboot (soft reset) the Z--otherwise the apps complain about not being able to find libkdemicro.so.3 (?), which is one of the libraries that the apps need. There is probably a more elegant way to solve this--running ldconfig or the like--but I forget the syntax off the top of my head.
Instead of "exploding" the app from the GUI, start up the terminal, and type:
bash-2.05$ kopi &
If you get an error saying "Can't find lib-something-or-other", you can probably reboot and it will solve it.