diff --git a/src/Rules.LXcray.mk b/src/Rules.LXcray.mk
index 2aca0f7ddf755f74a310dddcc92b95a577c574b2..d0b01dac5a34615afa2e22106090bb64ce6809f2 100644
--- a/src/Rules.LXcray.mk
+++ b/src/Rules.LXcray.mk
@@ -135,6 +135,14 @@ INC                += -I${GA_ROOT}/include
 LIBS               += -L${GA_ROOT}/lib -larmci -lga -lgfortran
 endif
 #
+# BITREP flags
+#
+#if MNH_BITREP exists => compile with the BITREP library
+MNH_BITREP = YES
+ifeq "$(MNH_BITREP)" "YES"
+CPPFLAGS_MNH += -DMNH_BITREP
+endif
+#
 # LIBTOOLS flags
 #
 #if MNH_TOOLS exists => compile the tools