diff --git a/mercurial/changegroup.py b/mercurial/changegroup.py
--- a/mercurial/changegroup.py
+++ b/mercurial/changegroup.py
@@ -482,7 +482,17 @@ class cg1packer(object):
         base = self.deltaparent(revlog, rev, p1, p2, prev)
 
         prefix = ''
-        if base == nullrev:
+        if revlog.iscensored(base) or revlog.iscensored(rev):
+            try:
+                delta = revlog.revision(node)
+            except error.CensoredNodeError, e:
+                delta = e.tombstone
+            if base == nullrev:
+                prefix = mdiff.trivialdiffheader(len(delta))
+            else:
+                baselen = revlog.rawsize(base)
+                prefix = mdiff.replacediffheader(baselen, len(delta))
+        elif base == nullrev:
             delta = revlog.revision(node)
             prefix = mdiff.trivialdiffheader(len(delta))
         else:
diff --git a/mercurial/error.py b/mercurial/error.py
--- a/mercurial/error.py
+++ b/mercurial/error.py
@@ -138,11 +138,15 @@ class ReadOnlyPartError(RuntimeError):
     pass
 
 class CensoredNodeError(RevlogError):
-    """error raised when content verification fails on a censored node"""
+    """error raised when content verification fails on a censored node
 
-    def __init__(self, filename, node):
+    Also contains the tombstone data substituted for the uncensored data.
+    """
+
+    def __init__(self, filename, node, tombstone):
         from node import short
         RevlogError.__init__(self, '%s:%s' % (filename, short(node)))
+        self.tombstone = tombstone
 
 class CensoredBaseError(RevlogError):
     """error raised when a delta is rejected because its base is censored
diff --git a/mercurial/filelog.py b/mercurial/filelog.py
--- a/mercurial/filelog.py
+++ b/mercurial/filelog.py
@@ -101,7 +101,7 @@ class filelog(revlog.revlog):
             super(filelog, self).checkhash(text, p1, p2, node, rev=rev)
         except error.RevlogError:
             if _censoredtext(text):
-                raise error.CensoredNodeError(self.indexfile, node)
+                raise error.CensoredNodeError(self.indexfile, node, text)
             raise
 
     def iscensored(self, rev):