--- a/mercurial/bookmarks.py	Mon Mar 14 20:53:55 2011 +0100
+++ b/mercurial/bookmarks.py	Mon Mar 14 23:03:56 2011 +0100
@@ -116,6 +116,15 @@
         wlock.release()
     repo._bookmarkcurrent = mark
 
+def updatecurrentbookmark(repo, oldnode, curbranch):
+    try:
+        update(repo, oldnode, repo.branchtags()[curbranch])
+    except KeyError:
+        if curbranch == "default": # no default branch!
+            update(repo, oldnode, repo.lookup("tip"))
+        else:
+            raise util.Abort(_("branch %s not found") % curbranch)
+
 def update(repo, parents, node):
     marks = repo._bookmarks
     update = False

--- a/mercurial/commands.py	Mon Mar 14 20:53:55 2011 +0100
+++ b/mercurial/commands.py	Mon Mar 14 23:03:56 2011 +0100
@@ -4038,15 +4038,16 @@
     fnames = (fname1,) + fnames
 
     lock = repo.lock()
+    wc = repo['.']
     try:
         for fname in fnames:
             f = url.open(ui, fname)
             gen = changegroup.readbundle(f, fname)
             modheads = repo.addchangegroup(gen, 'unbundle', 'bundle:' + fname,
                                            lock=lock)
+        bookmarks.updatecurrentbookmark(repo, wc.node(), wc.branch())
     finally:
         lock.release()
-
     return postincoming(ui, repo, modheads, opts.get('update'), None)
 
 def update(ui, repo, node=None, rev=None, clean=False, date=None, check=False):

--- a/tests/test-bookmarks.t	Mon Mar 14 20:53:55 2011 +0100
+++ b/tests/test-bookmarks.t	Mon Mar 14 23:03:56 2011 +0100
@@ -288,3 +288,36 @@
   2 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ hg -R cloned-bookmarks-rev bookmarks
      X2                        1:925d80f479bb
+
+create bundle with two heads
+
+  $ hg clone . tobundle
+  updating to branch default
+  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  $ echo x > tobundle/x
+  $ hg -R tobundle add tobundle/x
+  $ hg -R tobundle commit -m'x'
+  $ hg -R tobundle update -r -2
+  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
+  $ echo y > tobundle/y
+  $ hg -R tobundle branch test
+  marked working directory as branch test
+  $ hg -R tobundle add tobundle/y
+  $ hg -R tobundle commit -m'y'
+  $ hg -R tobundle bundle tobundle.hg
+  searching for changes
+  2 changesets found
+  $ hg unbundle tobundle.hg
+  adding changesets
+  adding manifests
+  adding file changes
+  added 2 changesets with 2 changes to 2 files (+1 heads)
+  (run 'hg heads' to see heads, 'hg merge' to merge)
+  $ hg update
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  $ hg bookmarks
+     X2                        1:925d80f479bb
+     Y                         2:db815d6d32e6
+   * Z                         3:125c9a1d6df6
+     x  y                      2:db815d6d32e6
+