diff --git a/glafp-utils/Makefile b/glafp-utils/Makefile
index 7d6207d5c71d1f0d064efad10361aac4b12b92f0..130eb79c52222cd5c5564ada7474913ecb5e1225 100644
--- a/glafp-utils/Makefile
+++ b/glafp-utils/Makefile
@@ -14,6 +14,6 @@ include $(TOP)/mk/boilerplate.mk
 #
 # ToDo: remove msub for good
 #
-SUBDIRS = mkdependC lndir ltx mkdirhier runstdtest sgmlverb
+SUBDIRS = mkdependC lndir ltx mkdirhier runstdtest sgmlverb docbook
 
 include $(TOP)/mk/target.mk