diff --git a/.gitmodules b/.gitmodules
index 87babf1..2a37d1c 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -46,3 +46,6 @@
 [submodule "docu/system_wiki"]
 	path = docu/system_wiki
 	url = ../system.wiki.git
+[submodule "lib/phpdoc_md"]
+	path = lib/phpdoc_md
+	url = ../lib_phpdoc_md.git
diff --git a/lib/phpdoc_md b/lib/phpdoc_md
new file mode 160000
index 0000000..6a52c6e
--- /dev/null
+++ b/lib/phpdoc_md
@@ -0,0 +1 @@
+Subproject commit 6a52c6e0529d005d07c9f58af2934b5752d13907