diff --git a/Make.rules b/Make.rules
index 11cccd12f8bb1f004e807bb66c33d01e4d07dfc5..3a1c2c107dee683009f89231840126a15565179e 100644
--- a/Make.rules
+++ b/Make.rules
@@ -84,7 +84,7 @@ INSTALL		:= install
 INSTALLDIR	:= $(INSTALL) -d
 
 CFLAGS		?= -g -O2
-CFLAGS_ALL	:= -Wall -Wstrict-prototypes -D_GNU_SOURCE -std=gnu99 -fPIC
+CFLAGS_ALL	:= -Wall -Wstrict-prototypes -D_GNU_SOURCE -D_FILE_OFFSET_BITS=64 -std=gnu99 -fPIC
 CFLAGS_ALL	+= $(CFLAGS)
 
 LDFLAGS		?= -g