I have a completely updated Gentoo Version, installed from Stage 1. KDE (Version 3.2) was emerged with "emerge kde". The connect button in krdc stays gray, not clickable. No connection is possible.
Created attachment 27365 [details] Snapshot of the application
It should be "rdp://". it looks like there is a typo in the Examples. You should forward that to the kde people so they know to fix it.