diff --git a/mercurial/bookmarks.py b/mercurial/bookmarks.py
--- a/mercurial/bookmarks.py
+++ b/mercurial/bookmarks.py
@@ -363,6 +363,11 @@ def compare(repo, srcmarks, dstmarks,
     return results
 
 def _diverge(ui, b, path, localmarks):
+    '''Return appropriate diverged bookmark for specified ``path``
+
+    This returns None, if it is failed to assign any divergent
+    bookmark name.
+    '''
     if b == '@':
         b = ''
     # find a unique @ suffix
@@ -370,6 +375,8 @@ def _diverge(ui, b, path, localmarks):
         n = '%s@%d' % (b, x)
         if n not in localmarks:
             break
+    else:
+        n = None
     # try to use an @pathalias suffix
     # if an @pathalias already exists, we overwrite (update) it
     if path.startswith("file:"):
@@ -411,9 +418,13 @@ def updatefromremote(ui, repo, remotemar
                             _("importing bookmark %s\n") % (b)))
         else:
             db = _diverge(ui, b, path, localmarks)
-            changed.append((db, bin(scid), warn,
-                            _("divergent bookmark %s stored as %s\n")
-                            % (b, db)))
+            if db:
+                changed.append((db, bin(scid), warn,
+                                _("divergent bookmark %s stored as %s\n") %
+                                (b, db)))
+            else:
+                warn(_("warning: failed to assign numbered name "
+                       "to divergent bookmark %s\n") % (b))
     for b, scid, dcid in adddst + advdst:
         if b in explicit:
             explicit.discard(b)
diff --git a/tests/test-bookmarks-pushpull.t b/tests/test-bookmarks-pushpull.t
--- a/tests/test-bookmarks-pushpull.t
+++ b/tests/test-bookmarks-pushpull.t
@@ -164,6 +164,27 @@ divergent bookmarks
      Z                         2:0d2164f0ce0d
      foo                       -1:000000000000
    * foobar                    1:9b140be10808
+
+(test that too many divergence of bookmark)
+
+  $ cat > $TESTTMP/seq.py <<EOF
+  > import sys
+  > for i in xrange(*[int(a) for a in sys.argv[1:]]):
+  >     print i
+  > EOF
+  $ python $TESTTMP/seq.py 1 100 | while read i; do hg bookmarks -r 000000000000 "X@${i}"; done
+  $ hg pull ../a
+  pulling from ../a
+  searching for changes
+  no changes found
+  warning: failed to assign numbered name to divergent bookmark X
+  divergent bookmark @ stored as @1
+  $ hg bookmarks | grep '^   X' | grep -v ':000000000000'
+     X                         1:9b140be10808
+     X@foo                     2:0d2164f0ce0d
+  $ python $TESTTMP/seq.py 1 100 | while read i; do hg bookmarks -d "X@${i}"; done
+  $ hg bookmarks -d "@1"
+
   $ hg push -f ../a
   pushing to ../a
   searching for changes