diff --git a/lib/dialogwizard/dialogwizard.py b/lib/dialogwizard/dialogwizard.py
index ef146c33..41e2cc77 100755
--- a/lib/dialogwizard/dialogwizard.py
+++ b/lib/dialogwizard/dialogwizard.py
@@ -6,13 +6,17 @@
 # Author: Antoine Durand-Gasselin <adg@crans.org>
 #
 
-from wizard import Step, PreviousStep, EndScenario
+from wizard import Step, PreviousStep, EndScenario, TryAgain
 from itertools import izip
 import dialog, time
 
 def really_quit(dico):
     raise EndScenario("game over!", data = dico)
 
+def error_handler(exc):
+    dialog.Dialog().msgbox('Erreur:', exc.__repr__())
+    raise TryAgain()
+
 class DialogStepGenerator():
     u"""This class defines a step, that will prompt the user for various
     fields."""
@@ -34,7 +38,7 @@ class DialogStepGenerator():
             for field in sform:
                 item = default.get(field['var'], dico.get(field['var'], ''))
                 field['item'] = item
-            rc, res = self.d.form(enonce, fields = sform, title=title, **kw)
+            rc, res = self.d.form(enonce % dico, fields = sform, title=title % dico, **kw)
             self._check_rc(rc)
             for field, val in izip (sform, res):
                 dico[field['var']] = val
@@ -51,7 +55,7 @@ class DialogStepGenerator():
                     if c.get('show_cond', lambda x : True)(dico):
                         schoix.append((c['label'], c['item']))
             print schoix
-            rc, res = self.d.menu(enonce, choices = schoix, title = title, **kw)
+            rc, res = self.d.menu(enonce % dico, choices = schoix, title = title % dico, **kw)
             self._check_rc(rc)
             dico[var] = res
             return dico
@@ -59,13 +63,13 @@ class DialogStepGenerator():
 
     def input_step(self, title, enonce, var, **kw):
         def fn(dico, default):
-            rc, res = self.d.inputbox(enonce, title = title, init = dico.get(var, ''), **kw)
+            rc, res = self.d.inputbox(enonce % dico, title = title % dico, init = dico.get(var, ''), **kw)
             self._check_rc(rc)
             dico[var] = res
             return dico
         return Step(fn)
 
-    def checklist_step(self, title, enonce, liste):
+    def checklist_step(self, title, enonce, liste, **kw):
         def fn(dico, default):
             sliste = []
             for c in liste:
@@ -78,7 +82,7 @@ class DialogStepGenerator():
                         if dico.get(c['var'], False): checked = 'on'
                         else: checked = 'off'
                         sliste.append((c['var'], c['item'], checked))
-            rc, res = self.d.checklist(enonce, title = title, choices = sliste, **kw)
+            rc, res = self.d.checklist(enonce % dico, title = title % dico, choices = sliste, **kw)
             self._check_rc(rc)
             for tag, item, status in liste:
                 if tag in res:
diff --git a/lib/dialogwizard/wizard.py b/lib/dialogwizard/wizard.py
index 26e5e19a..bbc486f3 100755
--- a/lib/dialogwizard/wizard.py
+++ b/lib/dialogwizard/wizard.py
@@ -33,8 +33,9 @@ class Step:
 class Scenario:
     u"""This class allows us to define scenarios."""
 
-    def __init__(self):
-        u"""empty scenario"""
+    def __init__(self)
+        u"""empty scenario, with an error handler (that takes an exception as
+        argument)"""
         self.steps = None
 
     def nest(self, step):
@@ -87,6 +88,8 @@ def step_scenario(step):
 def unit_scenario():
     return ( Scenario())
 
+def _relance(exc): raise exc
+
 class Running:
     u"""To run scenarios"""
 
@@ -94,11 +97,12 @@ class Running:
     steps = None
     stack = None
 
-    def __init__(self, scenario, env = {}):
+    def __init__(self, scenario, env = {}, handle = _relance):
         if not isinstance(scenario, Scenario):
             raise TypeError("Can only run Scenarios")
         accu = scenario.steps
         self.env = env
+        self.handle = handle
 
         # To avoid brain spots on the walls, we shall reverse the list
         # of steps.
@@ -157,6 +161,9 @@ class Running:
                     # We can update defaults
                     pass
 
+                except Exception, e:
+                    self.handle(e)
+
         else:
             # Should not be called
             raise "invalid step"