ns = jdomWriter.getExtensionNamespaces();
assertEquals(1, ns.length);
assertEquals("urn:myNs1", ns[0][0]);
assertEquals("urn:myNs2", ns[0][1]);
jdomWriter.pushExtensionNamespaces(new String[] { "urn:myNs3" });
ns = jdomWriter.getExtensionNamespaces();
assertEquals(2, ns.length);
assertEquals(2, ns[0].length);
assertEquals(1, ns[1].length);