diff --git a/mozilla/content/events/src/nsDOMEvent.cpp b/mozilla/content/events/src/nsDOMEvent.cpp
index b4bc84126f6..71bc563f1a2 100644
--- a/mozilla/content/events/src/nsDOMEvent.cpp
+++ b/mozilla/content/events/src/nsDOMEvent.cpp
@@ -225,7 +225,7 @@ NS_METHOD nsDOMEvent::GetScreenX(PRInt32* aScreenX)
 
   nsIWidget* parent = ((nsGUIEvent*)mEvent)->widget;
   //Add extra since loop will free one.
-  NS_ADDREF(parent);
+  NS_IF_ADDREF(parent);
   nsIWidget* tmp;
   while (nsnull != parent) {
     parent->GetBounds(bounds);
@@ -246,7 +246,7 @@ NS_METHOD nsDOMEvent::GetScreenY(PRInt32* aScreenY)
 
   nsIWidget* parent = ((nsGUIEvent*)mEvent)->widget;
   //Add extra since loop will free one.
-  NS_ADDREF(parent);
+  NS_IF_ADDREF(parent);
   nsIWidget* tmp;
   while (nsnull != parent) {
     parent->GetBounds(bounds);
diff --git a/mozilla/layout/events/src/nsDOMEvent.cpp b/mozilla/layout/events/src/nsDOMEvent.cpp
index b4bc84126f6..71bc563f1a2 100644
--- a/mozilla/layout/events/src/nsDOMEvent.cpp
+++ b/mozilla/layout/events/src/nsDOMEvent.cpp
@@ -225,7 +225,7 @@ NS_METHOD nsDOMEvent::GetScreenX(PRInt32* aScreenX)
 
   nsIWidget* parent = ((nsGUIEvent*)mEvent)->widget;
   //Add extra since loop will free one.
-  NS_ADDREF(parent);
+  NS_IF_ADDREF(parent);
   nsIWidget* tmp;
   while (nsnull != parent) {
     parent->GetBounds(bounds);
@@ -246,7 +246,7 @@ NS_METHOD nsDOMEvent::GetScreenY(PRInt32* aScreenY)
 
   nsIWidget* parent = ((nsGUIEvent*)mEvent)->widget;
   //Add extra since loop will free one.
-  NS_ADDREF(parent);
+  NS_IF_ADDREF(parent);
   nsIWidget* tmp;
   while (nsnull != parent) {
     parent->GetBounds(bounds);