Hi,
kdelibs4c2a and kdelibs4c2a-kde3 cannot be installed on the same system.
Why not?
kdelibs4c2a provides the old KDE3.5.10 version of various core functions;
these older versions may not function correctly when a Trinity application
is expecting to see the new version of those functions. A good example of
this is if an application uses a task tray icon; if the old library is
used the icon will not show up.
Hope this helps!
Tim