--- Makefile.orig	2015-10-01 02:48:15 UTC
+++ Makefile
@@ -56,7 +56,7 @@ clean:
 
 install:
 	mkdir -p $(INSTALLDIR)
-	${BSD_INSTALL_DATA} zip.cma zip.cmi gzip.cmi zip.mli gzip.mli libcamlzip.a $(INSTALLDIR)
+	${BSD_INSTALL_DATA} zip.cma zip.cmi gzip.cmi zip.mli gzip.mli zlib.cmi zlib.mli libcamlzip.a $(INSTALLDIR)
 	if test -f dllcamlzip.so; then \
 	  ${BSD_INSTALL_DATA} dllcamlzip.so $(INSTALLDIR); \
           installdir=$(INSTALLDIR); \
