A large class of kde applications have issues building properly on x86_64
because they have trouble finding qt (usually lib != lib64 assumptions, etc). 
The workaround is usually to either define env vars QTINC/QTLIB (or use
./configure --with-qt-includes/--with-qt-libraries) pointing to the right place.

A lot of duplicated/extra effort could be avoided if QTINC and QTLIB were
already (correctly) defined in /etc/profile.d/qt.(sh|csh), adding lines like

qt.sh:
# Qt initialization script (sh)
if [ -z "$QTDIR" ] ; then
  QTDIR=...
  QTINC="${QTDIR}/include"
  QTLIB="${QTDIR}/lib"
fi

qt.csh:
# Qt initialization script (csh)
if ( ! $?QTDIR ) then
  setenv QTDIR ...
  setenv QTINC "${QTDIR}/include"
  setenv QTLIB "${QTDIR}/lib"
endif