configuring back with cario, pkg-config

[Riccardo Mottola]

Hi,

I am trying to configure back with cairo on NetBSD 5.1. I have cairo 
installed

configure:9096: $? = 0
configure:9117: result: yes
configure:9925: checking Backend Server
configure:9927: result: x11
configure:9930: checking Backend Graphics
configure:9932: result: cairo
configure:9947: WARNING: can't find cairo, required for graphics=cairo!
configure:9954: Switching to art
configure:10037: WARNING: can't find libart, required for graphics=art
configure:10044: Switching to xlib

I suppose this is due to:
pkg-config script not be found
pkg-config script not be found
pkg-config script not be found
pkg-config script not be found
pkg-config script not be found

I installed pkg-config and everything goes smooth. Is pkg-configu thus a 
hard build-time dependency to properly detect cairo?

Riccardo