QMAKEFEATURES in a .pro

[luca]

Hi all,
I need to include QWT library to my project. I installed QWT and now I have the QWT root in /usr/local/qwt-6.0.1/ .

In documentation I read that to use QWT I need to set the QMAKEFEATURES:
@
QMAKEFEATURES += /usr/local/qwt-6.0.1/features
@

and to add to my .pro the following line:
@
CONFIG += qwt
@

The problem is that if I add QMAKEFEATURES definition in my .pro file it doesn't works while if I do this from a console it works:
@
cd myapp/src/
export QMAKEFEATURES=/usr/local/qwt-6.0.1/features
qmake
make
@

it seems that it's not possible to add QMAKEFEATURES to a .pro ...

Is there a solution?

It should be useful to add it to .pro to have a platform independent application.