diff --git a/neat/locals/overload/mhod/nlp.py b/neat/locals/overload/mhod/nlp.py
index 4aba5bf..aea6ee8 100644
--- a/neat/locals/overload/mhod/nlp.py
+++ b/neat/locals/overload/mhod/nlp.py
@@ -75,10 +75,11 @@ def build_constraint(otf, migration_time, ls, state_vector,
      :rtype: tuple(function, function, number)
     """
     def constraint(*m):
+        m_list = list(m)
         return float(migration_time +
                      time_in_state_n +
-                     ls[-1](state_vector, p, m)) / \
+                     ls[-1](state_vector, p, m_list)) / \
                (migration_time +
                 time_in_states +
-                sum(l(state_vector, p, m) for l in ls))
+                sum(l(state_vector, p, m_list) for l in ls))
     return (constraint, operator.le, otf)
diff --git a/tests/locals/overload/mhod/test_nlp.py b/tests/locals/overload/mhod/test_nlp.py
index a2d06e1..02c4a37 100644
--- a/tests/locals/overload/mhod/test_nlp.py
+++ b/tests/locals/overload/mhod/test_nlp.py
@@ -52,7 +52,7 @@ class Nlp(TestCase):
                  [0.3, -0.3]]
             m1 = mock('m1')
             m2 = mock('m2')
-            m = (m1, m2)
+            m = [m1, m2]
             container = mock('function container')
             expect(container).l0(state_vector, p, m).and_return(2).once()
             expect(container).l1(state_vector, p, m). \