diff --git a/biopet-framework/src/main/scala/nl/lumc/sasc/biopet/core/config/ConfigValue.scala b/biopet-framework/src/main/scala/nl/lumc/sasc/biopet/core/config/ConfigValue.scala
index 3fef4e9fb7f2592cc24b242f6dd1bd9ebb7b5c66..3963a683f69a4a5d44f1cb8576d49f3bc6379747 100644
--- a/biopet-framework/src/main/scala/nl/lumc/sasc/biopet/core/config/ConfigValue.scala
+++ b/biopet-framework/src/main/scala/nl/lumc/sasc/biopet/core/config/ConfigValue.scala
@@ -1,6 +1,6 @@
 package nl.lumc.sasc.biopet.core.config
 
-class ConfigValue(val requestIndex:ConfigValueIndex, val foundIndex:ConfigValueIndex, val value:Any) {
+class ConfigValue(val requestIndex:ConfigValueIndex, val foundIndex:ConfigValueIndex, val value:Any, val default: Boolean) {
   def getString = Configurable.any2string(value)
   def getInt = Configurable.any2int(value)
   def getDouble = Configurable.any2double(value)
@@ -8,14 +8,22 @@ class ConfigValue(val requestIndex:ConfigValueIndex, val foundIndex:ConfigValueI
   def getMap = Configurable.any2map(value)
   
   override def toString: String = {
-    var output = "requestIndex = " + requestIndex
-    if (foundIndex == null) output += "'not foundin config, used default'"
-    else output += ", foundIndex = " + foundIndex
+    var output = "key = " + requestIndex.key
     output += ", value = " + value
+    output += ", requestIndex = (" + requestIndex + ")"
+    if (foundIndex == null && !default) output += ", found on root of config"
+    else if(!default) output += ", foundIndex = (" + foundIndex + ")"
+    else output += ", default value is used"
+    
     return output
   }
 }
 
 object ConfigValue {
-  def apply(requestIndex:ConfigValueIndex, foundIndex:ConfigValueIndex, value:Any) = new ConfigValue(requestIndex,foundIndex,value)
+  def apply(requestIndex:ConfigValueIndex, foundIndex:ConfigValueIndex, value:Any) = {
+    new ConfigValue(requestIndex,foundIndex,value, false)
+  }
+  def apply(requestIndex:ConfigValueIndex, foundIndex:ConfigValueIndex, value:Any, default:Boolean) = {
+    new ConfigValue(requestIndex,foundIndex,value, default)
+  }
 }