diff --git a/Makefile.common b/Makefile.common
index 7675500..b0fc350 100644
--- a/Makefile.common
+++ b/Makefile.common
@@ -353,7 +353,7 @@ $(ARCHIVEFILE):
 	mkdir -p "${TEMPDIR}/${TREEPATH}" ;\
 	if [ -d ${CODEDIR} ] ; then cp -R "${CODEDIR}" "${TEMPDIR}/${TREEPATH}" ; fi ; \
 	if [ -e createlinks ] ; then cp createlinks "${TEMPDIR}/${TREEPATH}/." ; fi ; \
-	if [ -d additional ] ; then cp additional/* "${TEMPDIR}/${TREEPATH}/." ; fi ; \
+	if [ -d additional ] ; then cp -r additional/* "${TEMPDIR}/${TREEPATH}/." ; fi ; \
 	rm -f ${ARCHIVEFILE} ;\
 	tar -caf "${ARCHIVEFILE}" -C "${TEMPDIR}" "${TREEPATH}" ;\
 	ls -l ${ARCHIVEFILE} ;\