diff --git a/Core/src/ca/uqac/lif/cep/functions/ApplyFunction.java b/Core/src/ca/uqac/lif/cep/functions/ApplyFunction.java
index cb9fdd7f..3866f60c 100755
--- a/Core/src/ca/uqac/lif/cep/functions/ApplyFunction.java
+++ b/Core/src/ca/uqac/lif/cep/functions/ApplyFunction.java
@@ -172,6 +172,10 @@ public void associateTo(int id, NodeFunction f, int out_stream_index, int out_st
     public void associateToInput(int id, int in_stream_index, int in_stream_pos,
         int out_stream_index, int out_stream_pos)
     {
+    	if (in_stream_index > getInputArity())
+    	{
+    		System.out.println("EILLE");
+    	}
       if (m_eventTracker != null)
       {
         m_eventTracker.associateToInput(getId(), in_stream_index, m_inputCount,
@@ -183,7 +187,11 @@ public void associateToInput(int id, int in_stream_index, int in_stream_pos,
     public void associateToOutput(int id, int in_stream_index, int in_stream_pos,
         int out_stream_index, int out_stream_pos)
     {
-      // Nothing to do
+    	if (m_eventTracker != null)
+      {
+        m_eventTracker.associateToOutput(getId(), in_stream_index, m_inputCount,
+            out_stream_index, m_outputCount);
+      }
     }
 
     @Override
diff --git a/Core/src/ca/uqac/lif/cep/functions/Constant.java b/Core/src/ca/uqac/lif/cep/functions/Constant.java
index d0bdf9e9..a9690207 100755
--- a/Core/src/ca/uqac/lif/cep/functions/Constant.java
+++ b/Core/src/ca/uqac/lif/cep/functions/Constant.java
@@ -62,7 +62,7 @@ public void evaluate(Object[] inputs, Object[] outputs, Context context, EventTr
     outputs[0] = m_value;
     if (tracker != null)
     {
-      tracker.associateToOutput(-1, 0, 0, 0, 0);
+      tracker.associateToInput(-1, 0, 0, 0, 0);
     }
   }
 
diff --git a/Core/src/ca/uqac/lif/cep/functions/Cumulate.java b/Core/src/ca/uqac/lif/cep/functions/Cumulate.java
index c701f7d0..04ad43df 100755
--- a/Core/src/ca/uqac/lif/cep/functions/Cumulate.java
+++ b/Core/src/ca/uqac/lif/cep/functions/Cumulate.java
@@ -67,7 +67,7 @@ protected boolean compute(Object[] inputs, Object[] outputs)
             // ...and to the previous output event
             // -1 and -2 since the count has already been incremented by the
             // call to super.compute() above
-            associateToInput(j, m_outputCount - 2, k, m_outputCount - 1);
+            associateToOutput(j, m_outputCount - 2, k, m_outputCount - 1);
 
           }
         }
diff --git a/Core/src/ca/uqac/lif/cep/functions/StreamVariable.java b/Core/src/ca/uqac/lif/cep/functions/StreamVariable.java
index 1ae28c4a..5735ce59 100755
--- a/Core/src/ca/uqac/lif/cep/functions/StreamVariable.java
+++ b/Core/src/ca/uqac/lif/cep/functions/StreamVariable.java
@@ -108,7 +108,7 @@ public void evaluate(Object[] inputs, Object[] outputs, Context context, EventTr
     outputs[0] = inputs[m_index];
     if (tracker != null)
     {
-      tracker.associateToOutput(-1, m_index, 0, 0, 0);
+      tracker.associateToInput(-1, m_index, 0, 0, 0);
     }
   }