diff --git a/runtime/doc/Makefile b/runtime/doc/Makefile
index 7068943..3505c03 100644
--- a/runtime/doc/Makefile
+++ b/runtime/doc/Makefile
@@ -40,6 +40,7 @@
 	helphelp.txt \
 	howto.txt \
 	if_cscop.txt \
+	if_lua.txt \
 	if_mzsch.txt \
 	if_ole.txt \
 	if_perl.txt \
@@ -171,6 +172,7 @@
 	helphelp.html \
 	howto.html \
 	if_cscop.html \
+	if_lua.html \
 	if_mzsch.html \
 	if_ole.html \
 	if_perl.html \