diff --git a/src/sat.tac b/src/sat.tac
index f8380fa7..669907b2 100644
--- a/src/sat.tac
+++ b/src/sat.tac
@@ -409,6 +409,8 @@ class SAT(service.Service):
         if not import_name:
             import_name,(plugin_path, mod, plugin_info) = plugins_to_import.popitem()
         else:
+            if not import_name in plugins_to_import:
+                raise ImportError(_('Dependency plugin not found: [%s]') % import_name)
             plugin_path, mod, plugin_info = plugins_to_import.pop(import_name)
         dependencies = plugin_info.setdefault("dependencies",[])
         for dependency in dependencies: