diff --git a/documentation.mk b/documentation.mk
index f0fc3d9511085f30214c8765d19e8756e3bc9e30..29ee3b293306c7899c3405652c2d5b253114f20d 100644
--- a/documentation.mk
+++ b/documentation.mk
@@ -8,7 +8,7 @@ XSLTPROC_FLAGS = \
 
 XSLT_MAN = http://docbook.sourceforge.net/release/xsl/current/manpages/docbook.xsl
 
-#include gtk-doc.make
+include gtk-doc.make
 
 %.1: doc/%.xml
 	$(AM_V_GEN) $(XSLTPROC) $(XSLTPROC_FLAGS) $(XSLT_MAN) $<