In message <Pine.GSO.4.61.0504211433280.2414@rfhpc8317>Hubert Feyrer writes
>On Thu, 21 Apr 2005, Stuart Brooks wrote:
>> OS: Netbsd 1.6.1
>
>An obvious thing to try here is to see if it works in 2.0(.2), 3.0_BETA 
>and/or -current.

Nope. If the problem is what I suspect, it's deliberate, and (without
acutally checking) I beleive it goes back to CSRG days.  FreeBSD-4.x
had the same problem with PF_KEY sockets as NetBSD; though I don't
know how, or if, the problem was addressed there.