diff --git a/src/build_models/Makefile b/src/build_models/Makefile
--- a/src/build_models/Makefile
+++ b/src/build_models/Makefile
@@ -1,30 +1,32 @@
 # $Id$
 
+QMAKE = qmake
+
 all: plugin_auxingrowth plugin_leaf plugin_meinhardt plugin_test
 
 plugin_auxingrowth: Makefile.plugin_auxingrowth
 	make -f Makefile.plugin_auxingrowth
 
 Makefile.plugin_auxingrowth: plugin_auxingrowth.pro
-	qmake -makefile -o $@ $< 
+	$(QMAKE) -makefile -o $@ $< 
 
 plugin_leaf: Makefile.plugin_leaf
 	make -f Makefile.plugin_leaf
 
 Makefile.plugin_leaf: plugin_leaf.pro
-	qmake -makefile -o $@ $< 
+	$(QMAKE) -makefile -o $@ $< 
 
 plugin_meinhardt: Makefile.plugin_meinhardt
 	make -f Makefile.plugin_meinhardt
 
 Makefile.plugin_meinhardt: plugin_meinhardt.pro
-	qmake -makefile -o $@ $< 
+	$(QMAKE) -makefile -o $@ $< 
 
 plugin_test: Makefile.plugin_test
 	make -f Makefile.plugin_test
 
 Makefile.plugin_test: plugin_test.pro
-	qmake -makefile -o $@ $< 
+	$(QMAKE) -makefile -o $@ $< 
 
 clean:
 	make -f Makefile.plugin_auxingrowth clean