Patch from Andrzej:

Getdown is currently failing to create patch files because JarDiff is closing the outputstream. The attached patch comments it out, which seems to work.

src/main/java/com/threerings/getdown/tools/JarDiff.java

@@ -190,7 +190,7 @@ public class JarDiff implements JarDiffCodes
             }
 
             jos.finish();
-            jos.close();
+//            jos.close();
 
         } catch (IOException ioE){
             throw ioE;