Index: MODEL/Interaction_Models/Vertex.C
===================================================================
--- MODEL/Interaction_Models/Vertex.C	(revision 14232)
+++ MODEL/Interaction_Models/Vertex.C	(working copy)
@@ -90,9 +90,8 @@
     int hit = 1;
     if (hit) {
       //required by Interaction_Model_ADD due to small couplings
-      if (m_v4[i].Coupling(0)==Complex(0.,0.) && m_v4[i].Coupling(1)==Complex(0.,0.))
-	m_v4[i].on = 0;
-      else { 
+      m_v4[i].on = m_v4[i].CheckCoupling();
+      if (m_v4[i].on) { 
 	if(m_v4[i].nleg==4) {
 	  for (short int k=1;k<5;k++) {
 	    for (short int l=1;l<5;l++) {
@@ -129,8 +128,7 @@
     int hit = 1;
     if (hit) {
       //required by Interaction_Model_ADD due to small couplings
-      if (m_v[i].Coupling(0)==Complex(0.,0.) && m_v[i].Coupling(1)==Complex(0.,0.))
-	m_v[i].on = 0;
+      m_v[i].on = m_v[i].CheckCoupling();
       if (m_v[i].nleg==3) {  
 	for (short int k=1;k<4;k++) {
 	  for (short int l=1;l<4;l++) {
Index: MODEL/Interaction_Models/Single_Vertex.C
===================================================================
--- MODEL/Interaction_Models/Single_Vertex.C	(revision 14232)
+++ MODEL/Interaction_Models/Single_Vertex.C	(working copy)
@@ -30,6 +30,14 @@
   return cpl[i].Value();
 }
  
+int Single_Vertex::CheckCoupling() const
+{
+  for (size_t i(0);i<cpl.size();++i) 
+    if (cpl[i].Value()!=Complex(0.,0.)) return 1;
+  return 0;
+}
+
+
 // Operators
 Single_Vertex& Single_Vertex::operator=(const Single_Vertex& v) 
 {
Index: MODEL/Interaction_Models/Single_Vertex.H
===================================================================
--- MODEL/Interaction_Models/Single_Vertex.H	(revision 14232)
+++ MODEL/Interaction_Models/Single_Vertex.H	(working copy)
@@ -28,6 +28,7 @@
     ~Single_Vertex(); 
     
     Complex Coupling(size_t i) const;
+    int CheckCoupling() const;
     // operators
     Single_Vertex&       operator= (const Single_Vertex&);
     const bool           operator==(const Single_Vertex&);