diff --git a/rdf/src/nsRDFToolbarDataModelItem.cpp b/rdf/src/nsRDFToolbarDataModelItem.cpp
index 6ae144af5aae..5be0c88add20 100644
--- a/rdf/src/nsRDFToolbarDataModelItem.cpp
+++ b/rdf/src/nsRDFToolbarDataModelItem.cpp
@@ -110,6 +110,11 @@ nsRDFToolbarDataModelItem::GetParent(nsIDMItem*& pItem) const
     return nsRDFDataModelItem::GetParent(pItem);
 }
 
+NS_IMETHODIMP
+nsRDFToolbarDataModelItem::SetOpenState(PRBool open)
+{
+	return nsRDFDataModelItem::SetOpenState(open);
+}
 
 NS_IMETHODIMP
 nsRDFToolbarDataModelItem::GetStringPropertyValue(nsString& result, const nsString& property) const
diff --git a/rdf/src/nsRDFToolbarDataModelItem.h b/rdf/src/nsRDFToolbarDataModelItem.h
index 9b7f9458a0d0..2595b76d79b2 100644
--- a/rdf/src/nsRDFToolbarDataModelItem.h
+++ b/rdf/src/nsRDFToolbarDataModelItem.h
@@ -57,6 +57,7 @@ public:
     NS_IMETHOD GetParent(nsIDMItem*& pItem) const;
 
     // Setters
+	NS_IMETHOD SetOpenState(PRBool open);
 
     // Methods to query the data model for a specific item displayed within the widget.
     NS_IMETHOD GetStringPropertyValue(nsString& value, const nsString& itemProperty) const;
diff --git a/rdf/src/nsRDFTreeDataModelItem.cpp b/rdf/src/nsRDFTreeDataModelItem.cpp
index 2f3b1bad9aaf..6b51aeda63ce 100644
--- a/rdf/src/nsRDFTreeDataModelItem.cpp
+++ b/rdf/src/nsRDFTreeDataModelItem.cpp
@@ -114,6 +114,11 @@ nsRDFTreeDataModelItem::GetParent(nsIDMItem*& pItem) const
     return nsRDFDataModelItem::GetParent(pItem);
 }
 
+NS_IMETHODIMP
+nsRDFTreeDataModelItem::SetOpenState(PRBool open)
+{
+	return nsRDFDataModelItem::SetOpenState(open);
+}
 
 NS_IMETHODIMP
 nsRDFTreeDataModelItem::GetStringPropertyValue(nsString& result, const nsString& property) const
diff --git a/rdf/src/nsRDFTreeDataModelItem.h b/rdf/src/nsRDFTreeDataModelItem.h
index 839d8933fe07..de385daa6e38 100644
--- a/rdf/src/nsRDFTreeDataModelItem.h
+++ b/rdf/src/nsRDFTreeDataModelItem.h
@@ -57,6 +57,7 @@ public:
     NS_IMETHOD GetParent(nsIDMItem*& pItem) const;
 
     // Setters
+	NS_IMETHOD SetOpenState(PRBool open);
 
     // Methods to query the data model for a specific item displayed within the widget.
     NS_IMETHOD GetStringPropertyValue(nsString& value, const nsString& itemProperty) const;