diff --git a/scm-plugins/scm-hg-plugin/src/main/resources/sonia/scm/python/scmhooks.py b/scm-plugins/scm-hg-plugin/src/main/resources/sonia/scm/python/scmhooks.py
index e9a58d589f..73b5bfe083 100644
--- a/scm-plugins/scm-hg-plugin/src/main/resources/sonia/scm/python/scmhooks.py
+++ b/scm-plugins/scm-hg-plugin/src/main/resources/sonia/scm/python/scmhooks.py
@@ -78,8 +78,10 @@ def callHookUrl(ui, repo, hooktype, node):
       printMessages(ui, msg.splitlines(True))
     else:
       ui.warn( "ERROR: scm-hook failed with an unknown error\n" )
+    ui.traceback()
   except ValueError:
     ui.warn( "scm-hook failed with an exception\n" )
+    ui.traceback()
   return abort
 
 def callback(ui, repo, hooktype, node=None, source=None, pending=None, **kwargs):