Index: qwt-6.3.0/qwtconfig.pri
===================================================================
--- qwt-6.3.0.orig/qwtconfig.pri
+++ qwt-6.3.0/qwtconfig.pri
@@ -28,9 +28,9 @@ win32 {
     # QWT_INSTALL_PREFIX = C:/Qwt-$$QWT_VERSION-qt-$$QT_VERSION
 }
 
-QWT_INSTALL_DOCS      = $${QWT_INSTALL_PREFIX}/doc
-QWT_INSTALL_HEADERS   = $${QWT_INSTALL_PREFIX}/include
-QWT_INSTALL_LIBS      = $${QWT_INSTALL_PREFIX}/lib
+QWT_INSTALL_DOCS      = $$[QT_INSTALL_DOCS]/qwt6
+QWT_INSTALL_HEADERS   = $$[QT_INSTALL_HEADERS]/qwt6
+QWT_INSTALL_LIBS      = $$[QT_INSTALL_LIBS]
 
 ######################################################################
 # Designer plugin
@@ -42,14 +42,12 @@ QWT_INSTALL_LIBS      = $${QWT_INSTALL_P
 # runtime environment of designer/creator.
 ######################################################################
 
-QWT_INSTALL_PLUGINS   = $${QWT_INSTALL_PREFIX}/plugins/designer
-
 # linux distributors often organize the Qt installation
 # their way and QT_INSTALL_PREFIX doesn't offer a good
 # path. Also QT_INSTALL_PREFIX is only one of the default
 # search paths of the designer - not the Qt creator
 
-#QWT_INSTALL_PLUGINS   = $$[QT_INSTALL_PREFIX]/plugins/designer
+QWT_INSTALL_PLUGINS   = $$[QT_INSTALL_PLUGINS]/designer
 
 ######################################################################
 # Features
@@ -63,8 +61,7 @@ QWT_INSTALL_PLUGINS   = $${QWT_INSTALL_P
 # with every Qt upgrade.
 ######################################################################
 
-QWT_INSTALL_FEATURES  = $${QWT_INSTALL_PREFIX}/features
-# QWT_INSTALL_FEATURES  = $$[QT_INSTALL_PREFIX]/features
+QWT_INSTALL_FEATURES  = $$[QMAKE_MKSPECS]/features
 
 ######################################################################
 # Build the static/shared libraries.