diff --git a/src/modules/Gz/zlibmod.c b/src/modules/Gz/zlibmod.c
index c52373cfda8abbe45559f5126debc362bf8f2e66..5a9551f0b57014b868b2bd9a101e757f846f56c2 100644
--- a/src/modules/Gz/zlibmod.c
+++ b/src/modules/Gz/zlibmod.c
@@ -4,7 +4,7 @@
 ||| See the files COPYING and DISCLAIMER for more information.
 \*/
 #include "global.h"
-RCSID("$Id: zlibmod.c,v 1.6 1997/03/22 21:18:38 grubba Exp $");
+RCSID("$Id: zlibmod.c,v 1.7 1997/04/07 03:26:31 hubbe Exp $");
 
 #include "zlib_machine.h"
 #include "types.h"
@@ -370,6 +370,12 @@ void pike_module_init(void)
   set_exit_callback(exit_gz_inflate);
 
   end_class("inflate",0);
+
+  add_integer_constant("NO_FLUSH",Z_NO_FLUSH,0);
+  add_integer_constant("PARTIAL_FLUSH",Z_PARTIAL_FLUSH,0);
+  add_integer_constant("SYNC_FLUSH",Z_SYNC_FLUSH,0);
+  add_integer_constant("FINISH",Z_FINISH,0);
+
 #endif
 }