diff --git a/qwtconfig.pri b/qwtconfig.pri
index 7adefe2..bc31815 100644
--- a/qwtconfig.pri
+++ b/qwtconfig.pri
@@ -19,13 +19,15 @@ QWT_VERSION      = $${QWT_VER_MAJ}.$${QWT_VER_MIN}.$${QWT_VER_PAT}
 QWT_INSTALL_PREFIX = $$[QT_INSTALL_PREFIX]
 
 unix {
-    QWT_INSTALL_PREFIX    = /usr/local/qwt-$$QWT_VERSION
+    # QWT_INSTALL_PREFIX    = /usr/local/qwt-$$QWT_VERSION
     # QWT_INSTALL_PREFIX = /usr/local/qwt-$$QWT_VERSION-qt-$$QT_VERSION
+    QWT_INSTALL_PREFIX = $$(PREFIX)
 }
 
 win32 {
-    QWT_INSTALL_PREFIX    = C:/Qwt-$$QWT_VERSION
+    #QWT_INSTALL_PREFIX    = C:/Qwt-$$QWT_VERSION
     # QWT_INSTALL_PREFIX = C:/Qwt-$$QWT_VERSION-qt-$$QT_VERSION
+    QWT_INSTALL_PREFIX = $$(LIBRARY_PREFIX)
 }
 
 QWT_INSTALL_DOCS      = $${QWT_INSTALL_PREFIX}/doc
@@ -42,14 +44,14 @@ QWT_INSTALL_LIBS      = $${QWT_INSTALL_PREFIX}/lib
 # runtime environment of designer/creator.
 ######################################################################
 
-QWT_INSTALL_PLUGINS   = $${QWT_INSTALL_PREFIX}/plugins/designer
+# QWT_INSTALL_PLUGINS   = $${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_PREFIX]/plugins/designer
 
 ######################################################################
 # Features
@@ -63,8 +65,8 @@ QWT_INSTALL_PLUGINS   = $${QWT_INSTALL_PREFIX}/plugins/designer
 # with every Qt upgrade. 
 ######################################################################
 
-QWT_INSTALL_FEATURES  = $${QWT_INSTALL_PREFIX}/features
-# QWT_INSTALL_FEATURES  = $$[QT_INSTALL_PREFIX]/features
+# QWT_INSTALL_FEATURES  = $${QWT_INSTALL_PREFIX}/features
+QWT_INSTALL_FEATURES  = $$[QT_INSTALL_PREFIX]/mkspecs/features
 
 ######################################################################
 # Build the static/shared libraries.
