diff --git a/srcpkgs/libbonobo/template b/srcpkgs/libbonobo/template
index 887e4299950..a36dac8507a 100644
--- a/srcpkgs/libbonobo/template
+++ b/srcpkgs/libbonobo/template
@@ -30,6 +30,7 @@ Add_dependency run dbus-libs
 Add_dependency run libxml2
 Add_dependency build pkg-config
 Add_dependency build intltool
+Add_dependency build flex
 Add_dependency build ORBit2-devel
 Add_dependency build glib-devel
 Add_dependency build dbus-glib-devel