diff --git a/test/test_dyn_optiondescription.py b/test/test_dyn_optiondescription.py
index d5db882..5b830e5 100644
--- a/test/test_dyn_optiondescription.py
+++ b/test/test_dyn_optiondescription.py
@@ -291,6 +291,7 @@ def test_build_dyndescription_context():
     dod = DynOptionDescription('dod', '', [st], callback=return_list, callback_params={'': ((val1, False),)})
     od = OptionDescription('od', '', [dod, val1])
     cfg = Config(od)
+    cfg._impl_test = True
     assert str(cfg) == """[dodval1]
 [dodval2]
 val1 = ['val1', 'val2']"""
diff --git a/tiramisu/config.py b/tiramisu/config.py
index 167cd19..ac4048d 100644
--- a/tiramisu/config.py
+++ b/tiramisu/config.py
@@ -313,7 +313,8 @@ class SubConfig(object):
 
     def _find(self, bytype, byname, byvalue, first, type_='option',
               _subpath=None, check_properties=True, display_error=True,
-              force_permissive=False, only_path=undefined):
+              force_permissive=False, only_path=undefined,
+              only_option=undefined):
         """
         convenience method for finding an option that lives only in the subtree
 
@@ -344,8 +345,7 @@ class SubConfig(object):
         only_first = first is True and byvalue is None and \
             check_properties is None
         if only_path is not undefined:
-            option = self.unwrap_from_path(only_path)
-            options = [(only_path, option)]
+            options = [(only_path, only_option)]
         else:
             options = self.cfgimpl_get_description().impl_get_options_paths(
                 bytype, byname, _subpath, only_first,
@@ -676,8 +676,8 @@ class GroupConfig(_CommonConfig):
             except PropertiesOptionError:
                 pass
 
-    def find_firsts(self, byname=None, bypath=undefined, byvalue=undefined,
-                    type_='option', display_error=True):
+    def find_firsts(self, byname=None, bypath=undefined, byoption=undefined,
+                    byvalue=undefined, type_='option', display_error=True):
         """Find first not in current GroupConfig, but in each children
         """
         ret = []
@@ -691,6 +691,8 @@ class GroupConfig(_CommonConfig):
                                     check_properties=False,
                                     display_error=display_error)
                 byname = None
+                byoption = self.cfgimpl_get_description(
+                ).impl_get_opt_by_path(bypath)
         except AttributeError:
             return self._find_return_results([], True)
         for child in self._impl_children:
@@ -698,6 +700,7 @@ class GroupConfig(_CommonConfig):
                 if isinstance(child, GroupConfig):
                     ret.extend(child.find_firsts(byname=byname,
                                                  bypath=bypath,
+                                                 byoption=byoption,
                                                  byvalue=byvalue,
                                                  type_=type_,
                                                  display_error=False))
@@ -708,7 +711,8 @@ class GroupConfig(_CommonConfig):
                         f_type = type_
                     f_ret = child._find(None, byname, byvalue, first=True,
                                         type_=f_type, display_error=False,
-                                        only_path=bypath)
+                                        only_path=bypath,
+                                        only_option=byoption)
                     if type_ == 'config':
                         ret.append(child)
                     else: