Commercial SDK Ubuntu : compilation with minimal options issues error message and quits

qt-linux-commercial-5.1.0-rc1-x86_64-offline-2013-06-12-87.run

Compilation with minimal options fails:
Error message:QXcbWindow: Unhandled client message: "_GTK_LOAD_ICONTHEMES"

Last log lines of the compile process:
g++ Wl,-no-undefined -Wl,-rpath,/home/nico/Qt5.1.0/5.1.0-rc1/Src/qtbase/lib -shared -o libqxcb.so .obj/debug-shared/qxcbclipboard.o .obj/debug-shared/qxcbconnection.o .obj/debug-shared/qxcbintegration.o .obj/debug-shared/qxcbkeyboard.o .obj/debug-shared/qxcbmime.o .obj/debug-shared/qxcbdrag.o .obj/debug-shared/qxcbscreen.o .obj/debug-shared/qxcbwindow.o .obj/debug-shared/qxcbbackingstore.o .obj/debug-shared/qxcbwmsupport.o .obj/debug-shared/main.o .obj/debug-shared/qxcbnativeinterface.o .obj/debug-shared/qxcbcursor.o .obj/debug-shared/qxcbimage.o .obj/debug-shared/qxcbxsettings.o .obj/debug-shared/qxcbconnection_xi2.o .obj/debug-shared/qglxintegration.o .obj/debug-shared/atom.o .obj/debug-shared/xkb-compat.o .obj/debug-shared/context.o .obj/debug-shared/xkb-keymap.o .obj/debug-shared/keysym.o .obj/debug-shared/keysym-utf.o .obj/debug-shared/state.o .obj/debug-shared/text.o .obj/debug-shared/action.o .obj/debug-shared/ast-build.o .obj/debug-shared/compat.o .obj/debug-shared/expr.o .obj/debug-shared/include.o .obj/debug-shared/keycodes.o .obj/debug-shared/keymap-dump.o .obj/debug-shared/keymap.o .obj/debug-shared/parser.o .obj/debug-shared/rules.o .obj/debug-shared/scanner.o .obj/debug-shared/symbols.o .obj/debug-shared/types.o .obj/debug-shared/vmod.o .obj/debug-shared/xkbcomp.o .obj/debug-shared/moc_qxcbconnection.o .obj/debug-shared/moc_qxcbmime.o .obj/debug-shared/moc_qxcbnativeinterface.o -lX11-xcb -lXi -lxcb-render-util -ldl -lxcb-glx -lxcb-render -ldbus-1 -lxcb -lxcb-image -lxcb-icccm -lxcb-sync -lxcb-xfixes -lxcb-shm -lxcb-randr -lxcb-shape -lxcb-keysyms -L/home/nico/Qt5.1.0/5.1.0-rc1/Src/qtbase/lib -lQt5PlatformSupport -lfontconfig -lfreetype -pthread -lgthread-2.0 -lrt -lglib-2.0 -lXext -lX11 -lm -lXrender -lQt5DBus -lQt5Gui -lQt5Core -lGL -lpthread
mv -f libqxcb.so ../../../../plugins/platforms/

{ test -z "../../../../plugins/platforms/" || cd "../../../../plugins/platforms/"; }

&& test $(gdb --version | sed -e 's,[^0-9]+([0-9])\.([0-9]).*,\1\2,;q') -gt 72 && gdb --nx --batch --quiet -ex 'set confirm off' -ex "save gdb-index ." -ex quit 'libqxcb.so' && test -f libqxcb.so.gdb-index && objcopy --add-section '.gdb_index=libqxcb.so.gdb-index' --set-section-flags '.gdb_index=readonly' 'libqxcb.so' 'libqxcb.so' && rm -f libqxcb.so.gdb-index || true
make[5]: Leaving directory `/home/nico/Qt5.1.0/5.1.0-rc1/Src/qtbase/src/plugins/platforms/xcb'
make[4]: Leaving directory `/home/nico/Qt5.1.0/5.1.0-rc1/Src/qtbase/src/plugins/platforms/xcb'
make[3]: Leaving directory `/home/nico/Qt5.1.0/5.1.0-rc1/Src/qtbase/src/plugins/platforms'
make[2]: Leaving directory `/home/nico/Qt5.1.0/5.1.0-rc1/Src/qtbase/src/plugins'
make[1]: Leaving directory `/home/nico/Qt5.1.0/5.1.0-rc1/Src/qtbase/src'