diff --git a/src/Rules.LXcray.mk b/src/Rules.LXcray.mk
index 341a6101853c87d95ee2929f04f03bbeece24b22..10379a889ab92b9624383ddbed8ead0dab6c13c7 100644
--- a/src/Rules.LXcray.mk
+++ b/src/Rules.LXcray.mk
@@ -22,7 +22,7 @@ OPT_I8     =  -sinteger64
 OPT_R8     =  -sreal64
 #
 ifeq "$(VER_USER)" "ZSOLVER"
-CPPFLAGS  += -DCARTESIANGEOMETRY -DOVERLAPCOMMS -DPIECEWISELINEAR
+CPPFLAGS  += -DCARTESIANGEOMETRY -DPIECEWISELINEAR
 PROG_LIST += MG_MAIN MG_MAIN_MNH_ALL
 endif
 #