diff --git a/StImageViewer.pro b/StImageViewer.pro
index d1acba4..e8b4211 100644
--- a/StImageViewer.pro
+++ b/StImageViewer.pro
@@ -26,6 +26,8 @@ TEMPLATE = app
 
 INCLUDEPATH += ..
 
+DEFINES += ST_OBJECT_MEMORY=ObjectMemory2
+
 SOURCES +=\
     StImageViewer.cpp \
     StObjectMemory.cpp \