To answer your Subject line: xforms has not been maintained in around four years.
Qt4 gives more possibility to use on non-Unix and even non-X11 systems. Qt4 has better support for internationalization and many other user interface features. This lets LyX developers work on LyX specific features. > make[7]: Entering directory > `/home/slitt/junk/lyx-1.5.3/src/frontends/qt4/ui' > /usr/lib/qt3//bin/uic -tr lyx::qt_ AboutUi.ui -o AboutUi.h > uic: File generated with too recent version of Qt Designer (4.0 vs. 3.3.6) > make[7]: *** [AboutUi.h] Erro Even though you installed libqt4-devel, the above is using QT3. Run the ./configure --help to see if it has options for: --with-extra-prefix=/usr/lib/qt4 --with-qt4-dir=/usr/lib/qt4 --with-qt4-includes=/usr/lib/qt4/include --with-qt4-libraries=/usr/lib/qt4/lib Adjust as needed. Also try running ./configure with UIC defined in the environment: UIC=/usr/lib/qt4/bin/uic ./configure
