diff --git a/mozilla/toolkit/profile/src/Makefile.in b/mozilla/toolkit/profile/src/Makefile.in
index e8cf7990276..04f11ce712b 100644
--- a/mozilla/toolkit/profile/src/Makefile.in
+++ b/mozilla/toolkit/profile/src/Makefile.in
@@ -62,6 +62,8 @@ CPPSRCS = \
 		nsToolkitProfileService.cpp \
 		$(NULL)
 
+DEFINES += -DIMPL_XREAPI
+
 GARBAGE += nsProfileLock.cpp
 
 include $(topsrcdir)/config/rules.mk