diff --git a/config/config.mak b/config/config.mak
index c3331fcf16da..2fee29f441ee 100644
--- a/config/config.mak
+++ b/config/config.mak
@@ -213,7 +213,7 @@ CFLAGS=$(CFLAGS) -DMOZ_FULLCIRCLE
 !endif
 
 !ifdef MODULAR_NETLIB
-CFLAGS=$(CFLAGS) -DMODULAR_NETLIB -DNS_MT_SUPPORTED -DNETLIB_THREAD -DNS_NET_FILE -DCookieManagement -DSingleSignon -DPrivacySiteInfo
+CFLAGS=$(CFLAGS) -DMODULAR_NETLIB -DNS_MT_SUPPORTED -DNETLIB_THREAD -DNS_NET_FILE -DCookieManagement -DPrivacySiteInfo
 !else
 # Defines for new cookie management...
 CFLAGS=$(CFLAGS) -DCookieManagement -DSingleSignon -DPrivacySiteInfo