Qml and translation

Hi. In order to have the texts to translate in my ts file I have to run lpupdate by hand, in this way:

/Dati/Qt/Qt5.4.0/5.4/gcc/bin/lupdate Qml/*.qml -ts DomusBossTouch_it.ts

I already have in my .pro file this lines of code:

lupdate_only

{ SOURCES = Qml\main.qml \ Qml\QQMain.qml \ Qml\QQServer.qml \ qcmainform.cpp }

but seems to have to effect. The only file that is managed by Tools -> External -> Linguist -> Update is qcmainform.cpp.