diff --git a/mercurial/cmdutil.py b/mercurial/cmdutil.py
--- a/mercurial/cmdutil.py
+++ b/mercurial/cmdutil.py
@@ -1203,6 +1203,9 @@ def showmarker(ui, marker):
         ui.write(' ')
         ui.write(hex(repl))
     ui.write(' %X ' % marker.flags())
+    parents = marker.parentnodes()
+    if parents is not None:
+        ui.write('{%s} ' % ', '.join(hex(p) for p in parents))
     ui.write('(%s) ' % util.datestr(marker.date()))
     ui.write('{%s}' % (', '.join('%r: %r' % t for t in
                                  sorted(marker.metadata().items())
diff --git a/tests/test-histedit-obsolete.t b/tests/test-histedit-obsolete.t
--- a/tests/test-histedit-obsolete.t
+++ b/tests/test-histedit-obsolete.t
@@ -90,7 +90,7 @@ Enable obsolete
   o  0:cb9a9f314b8b a
   
   $ hg debugobsolete
-  d2ae7f538514cd87c17547b0de4cea71fe1af9fb 0 (*) {'user': 'test'} (glob)
+  d2ae7f538514cd87c17547b0de4cea71fe1af9fb 0 {cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b} (*) {'user': 'test'} (glob)
   177f92b773850b59254aa5e923436f921b55483b b346ab9a313db8537ecf96fca3ca3ca984ef3bd7 0 (*) {'user': 'test'} (glob)
   055a42cdd88768532f9cf79daa407fc8d138de9b 59d9f330561fd6c88b1a6b32f0e45034d88db784 0 (*) {'user': 'test'} (glob)
   e860deea161a2f77de56603b340ebbb4536308ae 59d9f330561fd6c88b1a6b32f0e45034d88db784 0 (*) {'user': 'test'} (glob)
diff --git a/tests/test-rebase-obsolete.t b/tests/test-rebase-obsolete.t
--- a/tests/test-rebase-obsolete.t
+++ b/tests/test-rebase-obsolete.t
@@ -166,18 +166,18 @@ set.
   o  0:cd010b8cd998 A
   
   $ hg debugobsolete
-  42ccdea3bb16d28e1848c95fe2e44c000f3f21b1 0 (*) {'user': 'test'} (glob)
+  42ccdea3bb16d28e1848c95fe2e44c000f3f21b1 0 {cd010b8cd998f3981a5a8115f94f8da4ab506089} (*) {'user': 'test'} (glob)
   5fddd98957c8a54a4d436dfe1da9d87f21a1b97b 5ae4c968c6aca831df823664e706c9d4aa34473d 0 (*) {'user': 'test'} (glob)
-  32af7686d403cf45b5d95f2d70cebea587ac806a 0 (*) {'user': 'test'} (glob)
+  32af7686d403cf45b5d95f2d70cebea587ac806a 0 {5fddd98957c8a54a4d436dfe1da9d87f21a1b97b} (*) {'user': 'test'} (glob)
 
 
 More complex case were part of the rebase set were already rebased
 
   $ hg rebase --rev 'desc(D)' --dest 'desc(H)'
   $ hg debugobsolete
-  42ccdea3bb16d28e1848c95fe2e44c000f3f21b1 0 (*) {'user': 'test'} (glob)
+  42ccdea3bb16d28e1848c95fe2e44c000f3f21b1 0 {cd010b8cd998f3981a5a8115f94f8da4ab506089} (*) {'user': 'test'} (glob)
   5fddd98957c8a54a4d436dfe1da9d87f21a1b97b 5ae4c968c6aca831df823664e706c9d4aa34473d 0 (*) {'user': 'test'} (glob)
-  32af7686d403cf45b5d95f2d70cebea587ac806a 0 (*) {'user': 'test'} (glob)
+  32af7686d403cf45b5d95f2d70cebea587ac806a 0 {5fddd98957c8a54a4d436dfe1da9d87f21a1b97b} (*) {'user': 'test'} (glob)
   08483444fef91d6224f6655ee586a65d263ad34c 4596109a6a4328c398bde3a4a3b6737cfade3003 0 (*) {'user': 'test'} (glob)
   $ hg log -G
   @  11:4596109a6a43 D
@@ -200,12 +200,12 @@ More complex case were part of the rebas
   
   $ hg rebase --source 'desc(B)' --dest 'tip'
   $ hg debugobsolete
-  42ccdea3bb16d28e1848c95fe2e44c000f3f21b1 0 (*) {'user': 'test'} (glob)
+  42ccdea3bb16d28e1848c95fe2e44c000f3f21b1 0 {cd010b8cd998f3981a5a8115f94f8da4ab506089} (*) {'user': 'test'} (glob)
   5fddd98957c8a54a4d436dfe1da9d87f21a1b97b 5ae4c968c6aca831df823664e706c9d4aa34473d 0 (*) {'user': 'test'} (glob)
-  32af7686d403cf45b5d95f2d70cebea587ac806a 0 (*) {'user': 'test'} (glob)
+  32af7686d403cf45b5d95f2d70cebea587ac806a 0 {5fddd98957c8a54a4d436dfe1da9d87f21a1b97b} (*) {'user': 'test'} (glob)
   08483444fef91d6224f6655ee586a65d263ad34c 4596109a6a4328c398bde3a4a3b6737cfade3003 0 (*) {'user': 'test'} (glob)
   8877864f1edb05d0e07dc4ba77b67a80a7b86672 462a34d07e599b87ea08676a449373fe4e2e1347 0 (*) {'user': 'test'} (glob)
-  08483444fef91d6224f6655ee586a65d263ad34c 0 (*) {'user': 'test'} (glob)
+  08483444fef91d6224f6655ee586a65d263ad34c 0 {8877864f1edb05d0e07dc4ba77b67a80a7b86672} (*) {'user': 'test'} (glob)
   5ae4c968c6aca831df823664e706c9d4aa34473d 98f6af4ee9539e14da4465128f894c274900b6e5 0 (*) {'user': 'test'} (glob)
   $ hg log --rev 'divergent()'
   $ hg log -G