Rebuild kde4-ruby with the Qwt bindings

I would like to rebuild the kde4-ruby, which provides Qt bindings for Ruby, with the Qwt bindings turned on. I wasn’t able to turn this settings on: CMake always skips it.

(I know this question isn’t openSUSE specific but I couldn’t find help anywhere else)

When I ask Cake to create the makefiles:

vitorpy@myhost:~/qtruby/qt4-qtruby-2.1.0> cmake -DCMAKE_INSTALL_PREFIX=/opt/kde4 -DENABLE_SMOKE=on -DENABLE_QTRUBY=on -DENABLE_QWT_SMOKE=on -DENABLE_QWT_RUBY=on -DQwt5_INCLUDE_DIR=/usr/local/qwt-5.2.1/include -DQwt5_Qt4_LIBRARY=/usr/local/qwt-5.2.1/lib/libqwt.so

It skips it anyway:

-- Build Ruby bindings: QtRuby;QtScript;QtTest;QtUiTools;QtWebKit
-- Skip Ruby bindings: Akonadi;KHTML;KIO;KTextEditor;Korundum;KrossRuby;Nepomuk;Okular;Phonon;Plasma;QScintilla;Qwt;Solid;Soprano

Does someone have an idea of how should I proceed to make it build correctly? Afterwards, I would like to make this package available to the community: how should I do it?

Thanks in advance!