--- src/allmydata/test/test_dirnode.py-orig	2009-04-08 21:46:45.000000000 -0600
+++ src/allmydata/test/test_dirnode.py	2009-04-08 21:48:12.000000000 -0600
@@ -457,6 +457,15 @@
             d.addCallback(lambda res: n.get_metadata_for(u"c2"))
             d.addCallback(lambda metadata: self.failUnlessEqual(metadata.keys(), ['__sys']))
 
+            # You can't override the link timestamps.
+            d.addCallback(lambda res: n.set_uri(u"c2", fake_file_uri.to_string(), { '__sys': {'linkcrtime': "bogus"}}))
+            d.addCallback(lambda res: n.get_metadata_for(u"c2"))
+            def _has_good_linkcrtime(metadata):
+                self.failUnless(metadata.has_key('__sys'))
+                self.failUnless(metadata['__sys'].has_key('linkcrtime'))
+                self.failIfEqual(metadata['__sys']['linkcrtime'], 'bogus')
+            d.addCallback(_has_good_linkcrtime)
+
             # if we don't set any defaults, the child should get timestamps
             d.addCallback(lambda res: n.set_uri(u"c3", fake_file_uri.to_string()))
             d.addCallback(lambda res: n.get_metadata_for(u"c3"))
