diff --git a/cppu/source/uno/data.cxx b/cppu/source/uno/data.cxx
index 7b0ee22b7ba2..e2d8b6f4e5cd 100644
--- a/cppu/source/uno/data.cxx
+++ b/cppu/source/uno/data.cxx
@@ -36,6 +36,9 @@
 
 using namespace ::cppu;
 using namespace ::osl;
+#if OSL_DEBUG_LEVEL > 1
+using namespace ::rtl;
+#endif
 
 
 namespace cppu