$NetBSD$

--- jdk/make/common/Defs-bsd.gmk.orig	2010-01-11 16:46:18.000000000 +0000
+++ jdk/make/common/Defs-bsd.gmk
@@ -339,6 +339,14 @@ ifeq ($(OS_VENDOR), OpenBSD)
   SYSTEM_ZLIB = true
 endif
 
+ifeq ($(OS_VENDOR), NetBSD)
+  SYSTEM_ZLIB = true
+endif
+
+ifeq ($(OS_VENDOR), DragonFlyBSD)
+  SYSTEM_ZLIB = true
+endif
+
 #
 # Japanese manpages
 #
