diff -r fdc232d8a193 -r 987c31e2a08c mercurial/localrepo.py
--- a/mercurial/localrepo.py	Mon Aug 07 16:27:09 2006 -0500
+++ b/mercurial/localrepo.py	Mon Aug 07 16:47:06 2006 -0500
@@ -292,6 +292,10 @@
         try:
             return self.tags()[key]
         except KeyError:
+            if key == '.':
+                key = self.dirstate.parents()[0]
+                if key == nullid:
+                    raise repo.RepoError(_("no revision checked out"))
             try:
                 return self.changelog.lookup(key)
             except:
@@ -1693,6 +1697,7 @@
 
         return newheads - oldheads + 1
 
+
     def stream_in(self, remote):
         fp = remote.stream_out()
         resp = int(fp.readline())