diff --git a/otherlibs/systhreads/Makefile b/otherlibs/systhreads/Makefile
index 0910b31e8..12df1c797 100644
--- a/otherlibs/systhreads/Makefile
+++ b/otherlibs/systhreads/Makefile
@@ -16,7 +16,8 @@ LIB_OBJS=mutex.cmo iolock.cmo pervasives.cmo \
   $(LIB)/set.cmo $(LIB)/map.cmo $(LIB)/stack.cmo $(LIB)/queue.cmo \
   $(LIB)/stream.cmo $(LIB)/printf.cmo $(LIB)/format.cmo $(LIB)/arg.cmo \
   $(LIB)/printexc.cmo $(LIB)/gc.cmo $(LIB)/digest.cmo $(LIB)/random.cmo \
-  $(LIB)/oo.cmo $(LIB)/genlex.cmo $(LIB)/callback.cmo $(LIB)/weak.cmo
+  $(LIB)/oo.cmo $(LIB)/genlex.cmo $(LIB)/callback.cmo $(LIB)/weak.cmo \
+  $(LIB)/marshal.cmo
 
 THREAD_OBJS=thread.cmo condition.cmo event.cmo threadUnix.cmo
 
diff --git a/otherlibs/threads/Makefile b/otherlibs/threads/Makefile
index 97f706214..70b4d0a05 100644
--- a/otherlibs/threads/Makefile
+++ b/otherlibs/threads/Makefile
@@ -17,7 +17,8 @@ LIB_OBJS=pervasives.cmo \
   $(LIB)/set.cmo $(LIB)/map.cmo $(LIB)/stack.cmo $(LIB)/queue.cmo \
   $(LIB)/stream.cmo $(LIB)/printf.cmo $(LIB)/format.cmo $(LIB)/arg.cmo \
   $(LIB)/printexc.cmo $(LIB)/gc.cmo $(LIB)/digest.cmo $(LIB)/random.cmo \
-  $(LIB)/oo.cmo $(LIB)/genlex.cmo $(LIB)/callback.cmo $(LIB)/weak.cmo
+  $(LIB)/oo.cmo $(LIB)/genlex.cmo $(LIB)/callback.cmo $(LIB)/weak.cmo \
+  $(LIB)/marshal.cmo
 
 all: libthreads.a threads.cma stdlib.cma
 
@@ -55,6 +56,7 @@ install:
 	cd $(LIBDIR); $(RANLIB) libthreads.a
 	if test -d $(LIBDIR)/threads; then : ; else mkdir $(LIBDIR)/threads; fi
 	cp thread.cmi mutex.cmi condition.cmi event.cmi threadUnix.cmi threads.cma stdlib.cma $(LIBDIR)/threads
+	cp thread.mli mutex.mli condition.mli event.mli threadUnix.mli $(LIBDIR)
 
 installopt: