diff --git a/piklab-prog-qt4.spec b/piklab-prog-qt4.spec
index b2cc3ae..d7224e8 100644
--- a/piklab-prog-qt4.spec
+++ b/piklab-prog-qt4.spec
@@ -28,10 +28,10 @@ programmers.
 %setup -q -n piklab-%{version}
 
 %build
-export QTDIR=%_prefix/%{_lib}/qt4
-export LD_LIBRARY_PATH=$QTDIR/%{_lib}:$LD_LIBRARY_PATH
-export PATH=$QTDIR/bin:$PATH
-export TQTLIB=$QTDIR/%{_lib}
+export TQTDIR=%_prefix/%{_lib}/qt4
+export LD_LIBRARY_PATH=$TQTDIR/%{_lib}:$LD_LIBRARY_PATH
+export PATH=$TQTDIR/bin:$PATH
+export TQTLIB=$TQTDIR/%{_lib}
 cd %_builddir/%buildsubdir
 qmake piklab-prog.pro
 %make -j1