diff --git a/hgext/rebase.py b/hgext/rebase.py
--- a/hgext/rebase.py
+++ b/hgext/rebase.py
@@ -15,7 +15,7 @@ http://mercurial.selenic.com/wiki/Rebase
 '''
 
 from mercurial import hg, util, repair, merge, cmdutil, commands, bookmarks
-from mercurial import extensions, copies, patch
+from mercurial import extensions, patch
 from mercurial.commands import templateopts
 from mercurial.node import nullrev
 from mercurial.lock import release
@@ -215,7 +215,7 @@ def rebase(ui, repo, **opts):
                                         'resolve, then hg rebase --continue)'))
                     finally:
                         ui.setconfig('ui', 'forcemerge', '')
-                updatedirstate(repo, rev, target, p2)
+                cmdutil.duplicatecopies(repo, rev, target, p2)
                 if not collapsef:
                     newrev = concludenode(repo, rev, p1, p2, extrafn=extrafn)
                 else:
@@ -301,20 +301,6 @@ def checkexternal(repo, state, targetanc
                 external = p.rev()
     return external
 
-def updatedirstate(repo, rev, p1, p2):
-    """Keep track of renamed files in the revision that is going to be rebased
-    """
-    # Here we simulate the copies and renames in the source changeset
-    cop, diver = copies.copies(repo, repo[rev], repo[p1], repo[p2], True)
-    m1 = repo[rev].manifest()
-    m2 = repo[p1].manifest()
-    for k, v in cop.iteritems():
-        if k in m1:
-            if v in m1 or v in m2:
-                repo.dirstate.copy(v, k)
-                if v in m2 and v not in m1 and k in m2:
-                    repo.dirstate.remove(v)
-
 def concludenode(repo, rev, p1, p2, commitmsg=None, extrafn=None):
     'Commit the changes and store useful information in extra'
     try:
diff --git a/mercurial/cmdutil.py b/mercurial/cmdutil.py
--- a/mercurial/cmdutil.py
+++ b/mercurial/cmdutil.py
@@ -8,7 +8,7 @@
 from node import hex, nullid, nullrev, short
 from i18n import _
 import os, sys, errno, re, tempfile
-import util, scmutil, templater, patch, error, templatekw, revlog
+import util, scmutil, templater, patch, error, templatekw, revlog, copies
 import match as matchmod
 import subrepo
 
@@ -1176,6 +1176,19 @@ def add(ui, repo, match, dryrun, listsub
         bad.extend(f for f in rejected if f in match.files())
     return bad
 
+def duplicatecopies(repo, rev, p1, p2):
+    "Reproduce copies found in the source revision in the dirstate for grafts"
+    # Here we simulate the copies and renames in the source changeset
+    cop, diver = copies.copies(repo, repo[rev], repo[p1], repo[p2], True)
+    m1 = repo[rev].manifest()
+    m2 = repo[p1].manifest()
+    for k, v in cop.iteritems():
+        if k in m1:
+            if v in m1 or v in m2:
+                repo.dirstate.copy(v, k)
+                if v in m2 and v not in m1 and k in m2:
+                    repo.dirstate.remove(v)
+
 def commit(ui, repo, commitfunc, pats, opts):
     '''commit the specified files or all outstanding changes'''
     date = opts.get('date')