diff --git a/src/template/unixware b/src/template/unixware
index 9a3a902ecfb2e64087a7b30f37fae2e90f48bea8..4eabc5f4a643990224a85da71e0b34e04f88387d 100644
--- a/src/template/unixware
+++ b/src/template/unixware
@@ -11,4 +11,4 @@ fi
 
 SUPPORTS_THREADS=yes
 NEED_REENTRANT_FUNC_NAMES=yes
-THREAD_CFLAGS += "-D_REENTRANT"
+THREAD_CFLAGS = "$THREAD_CFLAGS -D_REENTRANT"