--- a/mercurial/wireproto.py	Fri Aug 29 12:28:58 2014 +0200
+++ b/mercurial/wireproto.py	Fri Aug 29 12:36:17 2014 +0200
@@ -202,6 +202,7 @@
 # :plain: string with no transformation needed.
 gboptsmap = {'heads':  'nodes',
              'common': 'nodes',
+             'obsmarkers': 'boolean',
              'bundlecaps': 'csv',
              'listkeys': 'csv',
              'cg': 'boolean'}