It occurred to me that Steven M. Bellovin wrote in gmane.os.netbsd.general:
> 	lintpkgsrc -i >/tmp/ood			# what's out of date
> 	pkgdepgraph -D /tmp/ood >/tmp/del	# ordered 'delete' list
> 	pkgdepgraph -R /tmp/ood >/tmp/reb	# 'rebuild' shell script

Alternatively, you might want to check out wip/pkgmanager, although the added
benefit of using wip/pkgmanager (You don't end up with a broken system
for 2 days, just because a bug in some basic library has been fixed, while
the calling API remains the same, so there's little point in rebuilding 
dependant packages anyway) might be small.

-- 
    Martijn van Buul - pino@dohd.org - http://www.stack.nl/~martijnb/
	 Geek code: G--  - Visit OuterSpace: mud.stack.nl 3333
 The most exciting phrase to hear in science, the one that heralds new
discoveries, is not 'Eureka!' (I found it!) but 'That's funny ...' Isaac Asimov