Updating gstreamer and question about tools dependency

["Blair Sadewitz" <blair.sadewitz%gmail.com@localhost>]

Hello,

The new GStreamer (0.10.20) desires flex>=2.5.31 (and yes, I think
this is genuinely required, but I'm not
positive).  On NetBSD, flex is a built-in tool; furthermore, as of now
we don't have any BUILDLINK_*_DEPENDS
entries in devel/flex/buildlink3.mk.

Is there a way (without resorting to writing my own rules to do this
within the package Makefile) to check the
version of flex provided by the base system before resorting to using
a pkgsrc-provided flex?  I thought
it would be nice to have pkgsrc do the "right thing" should NetBSD's
flex one day satisfy the dependency ...

Thanks,

--Blair