diff --git a/src/plugins/qt4projectmanager/qt4nodes.cpp b/src/plugins/qt4projectmanager/qt4nodes.cpp
index d6630eb3a68..033b12e5243 100644
--- a/src/plugins/qt4projectmanager/qt4nodes.cpp
+++ b/src/plugins/qt4projectmanager/qt4nodes.cpp
@@ -555,7 +555,7 @@ void Qt4PriFileNode::update(ProFile *includeFileExact, QtSupport::ProFileReader
     for (int i=0; i < folders.size(); ++i) {
         const QFileInfo fi(folders.at(i));
         if (fi.isRelative())
-            folders[i] = projectDir + '/' + folders.at(i);
+            folders[i] = QDir::cleanPath(projectDir + '/' + folders.at(i));
     }