diff --git a/src/gtk/notebook.cpp b/src/gtk/notebook.cpp
index 066b7dea59..76baec9d8e 100644
--- a/src/gtk/notebook.cpp
+++ b/src/gtk/notebook.cpp
@@ -649,7 +649,7 @@ bool wxNotebook::InsertPage( size_t position,
     nb_page->m_text = text;
     if (nb_page->m_text.IsEmpty()) nb_page->m_text = wxT("");
   
-    nb_page->m_label = GTK_LABEL( gtk_label_new(nb_page->m_text.mbc_str()) );
+    nb_page->m_label = GTK_LABEL( gtk_label_new(wxGTK_CONV(nb_page->m_text)) );
     gtk_box_pack_end( GTK_BOX(nb_page->m_box), GTK_WIDGET(nb_page->m_label), FALSE, FALSE, m_padding );
   
     /* show the label */
diff --git a/src/gtk1/notebook.cpp b/src/gtk1/notebook.cpp
index 066b7dea59..76baec9d8e 100644
--- a/src/gtk1/notebook.cpp
+++ b/src/gtk1/notebook.cpp
@@ -649,7 +649,7 @@ bool wxNotebook::InsertPage( size_t position,
     nb_page->m_text = text;
     if (nb_page->m_text.IsEmpty()) nb_page->m_text = wxT("");
   
-    nb_page->m_label = GTK_LABEL( gtk_label_new(nb_page->m_text.mbc_str()) );
+    nb_page->m_label = GTK_LABEL( gtk_label_new(wxGTK_CONV(nb_page->m_text)) );
     gtk_box_pack_end( GTK_BOX(nb_page->m_box), GTK_WIDGET(nb_page->m_label), FALSE, FALSE, m_padding );
   
     /* show the label */