diff -r c65113f3627a -r 8959700c2b19 mercurial/revlog.py
--- a/mercurial/revlog.py	Thu Feb 09 09:07:19 2006 +0100
+++ b/mercurial/revlog.py	Thu Feb 09 17:07:20 2006 -0600
@@ -828,6 +828,7 @@
 
         # then reset internal state in memory to forget those revisions
         self.cache = None
+        self.chunkcache = None
         for p in self.index[rev:]:
             del self.nodemap[p[6]]
         del self.index[rev:]