diff --git a/PackageKit.spec b/PackageKit.spec
index 11c19bb..8c39e74 100644
--- a/PackageKit.spec
+++ b/PackageKit.spec
@@ -32,7 +32,7 @@ Requires: preupgrade
 %endif
 
 # required by patch4
-BuildRequires: automake libtool
+BuildRequires: automake gtk-doc libtool
 BuildRequires: glib2-devel >= 2.16.1
 BuildRequires: dbus-devel  >= 1.1.1
 BuildRequires: dbus-glib-devel >= 0.74