diff --git a/netwerk/protocol/ftp/src/Makefile.in b/netwerk/protocol/ftp/src/Makefile.in
index 2030d5f16eb6..5fd1e62a950f 100644
--- a/netwerk/protocol/ftp/src/Makefile.in
+++ b/netwerk/protocol/ftp/src/Makefile.in
@@ -28,7 +28,7 @@ include $(DEPTH)/config/autoconf.mk
 
 MODULE		= necko
 LIBRARY_NAME	= nkftp_s
-REQUIRES	= xpcom string exthandler mime wallet dom layout widget
+REQUIRES	= xpcom string exthandler mime wallet dom layout widget pref
 
 CPPSRCS		= \
 		nsFtpProtocolHandler.cpp \