--- a/package_definition.xml	Thu Apr 29 11:55:32 2010 +0100
+++ b/package_definition.xml	Thu May 13 13:56:05 2010 +0100
@@ -1,10 +1,91 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<SystemDefinition schema="3.0.0">
-  <package id="podcatcher" name="Podcatcher" levels="app">
-    <collection id="podcatcher" name="Podcatcher" level="app">
-      <component id="podcatcher_build" filter="s60" name="Podcatcher Build">
-        <unit bldFile="group"/>
-      </component>
-    </collection>
-  </package>
+<!DOCTYPE SystemDefinition [
+<!ELEMENT SystemDefinition ( systemModel )>
+<!ATTLIST SystemDefinition
+  name CDATA #REQUIRED
+  schema CDATA #REQUIRED
+>
+<!-- all paths are relative to the environment variable specified by the root attribute, or SOURCEROOT if not.  -->
+
+<!-- System Model Section of DTD -->
+<!ELEMENT systemModel (layer+)>
+
+<!ELEMENT layer (block* | collection*)*>
+<!-- Kernel Services, Base Services, OS Services, Etc -->
+<!ATTLIST layer
+  name CDATA #REQUIRED
+  long-name CDATA #IMPLIED
+  levels NMTOKENS #IMPLIED
+  span CDATA #IMPLIED
+>
+
+<!ELEMENT block (subblock* | collection*)*>
+ <!-- Generic OS services, Comms Services, etc -->
+<!ATTLIST block
+  levels NMTOKENS #IMPLIED
+  span CDATA #IMPLIED
+  level NMTOKEN #IMPLIED
+  name CDATA #REQUIRED
+  long-name CDATA #IMPLIED
+>
+
+<!ELEMENT subblock (collection)*>
+<!-- Cellular Baseband Services, Networking Services, etc -->
+<!ATTLIST subblock
+  name CDATA #REQUIRED
+  long-name CDATA #IMPLIED
+>
+
+<!ELEMENT collection (component)*>
+<!-- Screen Driver, Content Handling, etc -->
+<!ATTLIST collection
+  name CDATA #REQUIRED
+  long-name CDATA #IMPLIED
+  level NMTOKEN #IMPLIED
+>
+
+<!ELEMENT component (unit)*>
+<!-- contains units or is a  package or prebuilt -->
+<!ATTLIST component
+  name CDATA #REQUIRED
+  long-name CDATA #IMPLIED
+  deprecated CDATA #IMPLIED
+  introduced CDATA #IMPLIED
+  contract CDATA #IMPLIED
+  plugin (Y|N) "N"
+  filter CDATA #IMPLIED
+  class NMTOKENS #IMPLIED
+  supports CDATA #IMPLIED
+  purpose ( optional | mandatory | development ) "optional"
+>
+
+<!ELEMENT unit EMPTY >
+<!-- must be buildable (bld.inf) -->
+<!-- bldFile  may someday be removed in favour of mrp -->
+<!ATTLIST unit
+  mrp CDATA #IMPLIED
+  filter CDATA #IMPLIED
+  bldFile CDATA #IMPLIED
+  root CDATA #IMPLIED
+  version NMTOKEN #IMPLIED
+  prebuilt NMTOKEN #IMPLIED
+  late (Y|N) #IMPLIED
+  priority CDATA #IMPLIED
+>
+]>
+<SystemDefinition name="Symbian^3" schema="2.0.1">
+  <systemModel>
+    <layer name="app" long-name="Applications" levels="apps">
+      <block name="podcatcher" level="app" long-name="Podcatcher" levels="apps">
+        <collection name="podcatcher_collection" long-name="Podcatcher Collection" level="app">
+          <component name="podcatcher_engine" long-name="Podcatcher Engine">
+            <unit bldFile="/sf/app/podcatcher/engine/group"/>
+          </component>
+          <component name="podcatcher_avkon_ui" long-name="Podcatcher Avkon UI">
+            <unit bldFile="/sf/app/podcatcher/application/group"/>
+          </component>
+        </collection>
+      </block>
+    </layer>
+  </systemModel>
 </SystemDefinition>