diff --git a/lang/ipython/Makefile b/lang/ipython/Makefile
index 4023fa0c3..dd1a908b3 100644
--- a/lang/ipython/Makefile
+++ b/lang/ipython/Makefile
@@ -46,13 +46,13 @@ define Build/Compile
 endef
 
 define Build/InstallDev
-	mkdir -p $(1)
-	cp -r $(PKG_INSTALL_DIR)/* $(1)
+	$(INSTALL_DIR) $(1)
+	$(CP) $(PKG_INSTALL_DIR)/* $(1)/
 endef
 
 define Package/ipython/install
-	mkdir -p $(1)
-	cp -r $(PKG_INSTALL_DIR)/* $(1)
+	$(INSTALL_DIR) $(1)
+	$(CP) $(PKG_INSTALL_DIR)/* $(1)/
 endef
 
 $(eval $(call BuildPackage,ipython))
diff --git a/lang/logilab-common/Makefile b/lang/logilab-common/Makefile
index 2fdce18c1..7478f54fd 100644
--- a/lang/logilab-common/Makefile
+++ b/lang/logilab-common/Makefile
@@ -37,8 +37,8 @@ define Build/Compile
 endef
 
 define Package/logilab-common/install
-	mkdir -p $(1)
-	cp -r $(PKG_INSTALL_DIR)/* $(1)/
+	$(INSTALL_DIR) $(1)
+	$(CP) $(PKG_INSTALL_DIR)/* $(1)/
 endef
 
 $(eval $(call BuildPackage,logilab-common))
diff --git a/lang/numpy/Makefile b/lang/numpy/Makefile
index 550b47bdf..1b2915ee7 100644
--- a/lang/numpy/Makefile
+++ b/lang/numpy/Makefile
@@ -35,8 +35,8 @@ define Build/Compile
 endef
 
 define Package/numpy/install
-	mkdir -p $(1)
-	cp -r $(PKG_INSTALL_DIR)/* $(1)
+	$(INSTALL_DIR) $(1)
+	$(CP) $(PKG_INSTALL_DIR)/* $(1)/
 endef
 
 define Require/python25-dev