diff --git a/src/debian6-i386.cfg b/src/debian6-i386.cfg
index 08d2513..2790127 100644
--- a/src/debian6-i386.cfg
+++ b/src/debian6-i386.cfg
@@ -1,3 +1,6 @@
+[debian6-i386.cfg]
+parts = ${debian6.cfg:parts}
+
 [buildout]
 extends = debian6.cfg
 
diff --git a/src/debian6.cfg b/src/debian6.cfg
index 9bfee36..973f26e 100644
--- a/src/debian6.cfg
+++ b/src/debian6.cfg
@@ -1,13 +1,15 @@
+[debian6.cfg]
+parts = cp27-install
+	cp33-install
+	pp27-install
+	jy25-install
+	jy25-install-as-jython
+	jy27-install
+
 [buildout]
 extends = cp27.cfg
 	  cp33.cfg
 	  pp27.cfg
 	  jy25.cfg
 	  jy27.cfg
-
-parts += cp27-install
-	 cp33-install
-	 pp27-install
-	 jy25-install
-	 jy25-install-as-jython
-	 jy27-install
+parts = ${debian6.cfg:parts}
diff --git a/src/debian7-i386.cfg b/src/debian7-i386.cfg
index 328c94c..5f2a5f6 100644
--- a/src/debian7-i386.cfg
+++ b/src/debian7-i386.cfg
@@ -1,3 +1,6 @@
+[debian7-i386.cfg]
+parts = ${debian7.cfg:parts}
+
 [buildout]
 extends = debian7.cfg
 
diff --git a/src/debian7.cfg b/src/debian7.cfg
index af43731..2de830a 100644
--- a/src/debian7.cfg
+++ b/src/debian7.cfg
@@ -1,3 +1,12 @@
+[debian7.cfg]
+parts = cp25-install
+	cp33-install
+	pp27-install
+        libssl0.9.8-install
+	jy25-install
+	jy25-install-as-jython
+	jy27-install
+
 [buildout]
 extends = cp25.cfg
 	  cp33.cfg
@@ -5,11 +14,4 @@ extends = cp25.cfg
           libssl0.9.8.cfg
 	  jy25.cfg
 	  jy27.cfg
-
-parts += cp25-install
-	 cp33-install
-	 pp27-install
-         libssl0.9.8-install
-	 jy25-install
-	 jy25-install-as-jython
-	 jy27-install
+parts = ${debian7.cfg:parts}
diff --git a/src/ubuntu-12.04-x86_64.cfg b/src/ubuntu-12.04-x86_64.cfg
index 262a168..e75bea7 100644
--- a/src/ubuntu-12.04-x86_64.cfg
+++ b/src/ubuntu-12.04-x86_64.cfg
@@ -1,3 +1,6 @@
+[ubuntu-12.04-x86_64.cfg]
+parts = ${ubuntu-12.04.cfg:parts}
+
 [buildout]
 extends = ubuntu-12.04.cfg
 
diff --git a/src/ubuntu-12.04.cfg b/src/ubuntu-12.04.cfg
index 0a2ebf3..248c4a0 100644
--- a/src/ubuntu-12.04.cfg
+++ b/src/ubuntu-12.04.cfg
@@ -1,13 +1,15 @@
+[ubuntu-12.04.cfg]
+parts = cp25-install
+	cp33-install
+	pp27-install
+	jy25-install
+	jy25-install-as-jython
+	jy27-install
+
 [buildout]
 extends = cp25.cfg
 	  cp33.cfg
 	  pp27.cfg
 	  jy25.cfg
 	  jy27.cfg
-
-parts += cp25-install
-	 cp33-install
-	 pp27-install
-	 jy25-install
-	 jy25-install-as-jython
-	 jy27-install
+parts = ${ubuntu-12.04.cfg:parts}