diff --git a/toolkit/library/libxul-rules.mk b/toolkit/library/libxul-rules.mk
index 2fbdc3157fb..567ca0c75b8 100644
--- a/toolkit/library/libxul-rules.mk
+++ b/toolkit/library/libxul-rules.mk
@@ -75,7 +75,7 @@ DEFINES += \
 
 ifeq ($(MOZ_WIDGET_TOOLKIT),windows)
 ifneq ($(OS_ARCH),WINCE)
-OS_LIBS += $(call EXPAND_LIBNAME,usp10)
+OS_LIBS += $(call EXPAND_LIBNAME,usp10 oleaut32)
 endif
 endif
 ifneq (,$(filter $(MOZ_WIDGET_TOOLKIT),mac cocoa))