I tried to install kde4 and it stops here.
/usr/ports/x11/kdebase4-runtime/work/kdebase-runtime-4.2.0/nepomuk/strigibackend/sopranoindexreader.cpp: In member function 'virtual void Strigi::Soprano::IndexReader::getChildren(const std::string&, std::map<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, int, std::less<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<std:
air<const std::basic_string<char, std::char_traits<char>, std::allocator<char> >, int> > >&)':
/usr/ports/x11/kdebase4-runtime/work/kdebase-runtime-4.2.0/nepomuk/strigibackend/sopranoindexreader.cpp:398: error: 'class Soprano::Node' has no member named 'toN3'
*** Error code 1
Stop in /usr/ports/x11/kdebase4-runtime/work/kdebase-runtime-4.2.0/build.
*** Error code 1
Stop in /usr/ports/x11/kdebase4-runtime/work/kdebase-runtime-4.2.0/build.
*** Error code 1
Stop in /usr/ports/x11/kdebase4-runtime/work/kdebase-runtime-4.2.0/build.
*** Error code 1
Stop in /usr/ports/x11/kdebase4-runtime.
*** Error code 1
Stop in /usr/ports/x11/kdebase4-runtime.
*** Error code 1
Stop in /usr/ports/x11/kde4.
*** Error code 1
Stop in /usr/ports/x11/kde4.