diff --git a/calendar/sunbird/app/Makefile.in b/calendar/sunbird/app/Makefile.in
index e5a78afad84e..31f406c913c2 100644
--- a/calendar/sunbird/app/Makefile.in
+++ b/calendar/sunbird/app/Makefile.in
@@ -63,6 +63,8 @@ REQUIRES = \
 
 CPPSRCS = nsCalendarApp.cpp
 
+LOCAL_INCLUDES += -I$(topsrcdir)/toolkit/xre
+
 ifdef BUILD_STATIC_LIBS
 STATIC_COMPONENTS_LINKER_PATH = -L$(DIST)/lib/components
 endif