Based on your preference, set KDE_PREFIX.
If KDE is your desktop of choice:
export KDE_PREFIX=/usr
If you want to try-out KDE:
export KDE_PREFIX=/opt/kde-3.3.2
Remember to execute ldconfig after installation of libraries to update the library cache.
If you are not installing KDE in /usr, you will need to make some configuration changes:
You should consider installing the desktop-file-utils-0.10 package. Though not required, this package will allow you to easily use existing .desktop files in /usr/share/applications (and any other locations identified by XDG_DATA_DIRS), and automatically add these applications to the KDE menu system.
Add to your system or personal profile:
export PATH=$PATH:/opt/kde-3.3.2/bin
export PKG_CONFIG_PATH=$PKG_CONFIG_PATH:/opt/kde-3.3.2/lib/pkgconfig
Add to your /etc/ld.so.conf:
cat >> /etc/ld.so.conf << "EOF" # Begin kde addition to /etc/ld.so.conf /opt/kde-3.3.2/lib # End kde addition EOF
Add to your /etc/man.conf:
cat >> /etc/man.conf << "EOF" # Begin kde addition to man.conf MANPATH /opt/kde-3.3.2/man # End kde addition to man.conf EOF
If you prefer installing KDE in /opt, one trick to avoid the above configuration changes every time you install a new version is to replace /opt/kde-3.3.2 with /opt/kde and to create a symlink from /opt/kde-3.3.2 to /opt/kde.
ln -sf kde-3.3.2 /opt/kde