diff --git a/contrib/sdk/sources/zlib/Tupfile.lua b/contrib/sdk/sources/zlib/Tupfile.lua
index 46301d889b..8c22a64d49 100755
--- a/contrib/sdk/sources/zlib/Tupfile.lua
+++ b/contrib/sdk/sources/zlib/Tupfile.lua
@@ -3,7 +3,12 @@ HELPERDIR = (tup.getconfig("HELPERDIR") == "") and "../../../../programs" or tup
 tup.include(HELPERDIR .. "/use_gcc.lua")
 tup.include(HELPERDIR .. "/use_newlib.lua")
 
+LDFLAGS = " -shared -s -T dll.lds --entry _DllStartup --image-base=0 --out-implib ../../lib/libz.dll.a "
+
 CFLAGS = CFLAGS .. " -DHAVE_UNISTD_H -U_Win32 -U_WIN32 -U__MINGW32__"
 
 compile_gcc{"adler32.c", "compress.c", "crc32.c", "deflate.c", "gzclose.c", "gzlib.c", "gzread.c", "gzwrite.c", "infback.c", "inffast.c", "inflate.c", "inftrees.c", "trees.c", "uncompr.c", "zutil.c"}
-tup.rule(OBJS, "kos32-ar rcs %o %f", {"../../lib/libz.a", "../../lib/<libz>"})
+--tup.rule(OBJS, "kos32-ar rcs %o %f", {"../../lib/libz.a", "../../lib/<libz>"})
+
+tup.rule(OBJS, "kos32-ld zlib.def" .. LDFLAGS ..  "-o %o %f -lgcc -lc.dll -ldll " .. tup.getconfig("KPACK_CMD"),
+  {"../../bin/libz.dll", extra_outputs = {"../../lib/libz.dll.a", "../../lib/<libz.dll.a>"}})