On Fri, Feb 09, 2007 at 02:09:19PM +0000, Matthias Scheler wrote:
> On Thu, Feb 08, 2007 at 10:27:05PM +1100, Alasdair wrote:
> > I finally worked out(?) that it is a problem with a router that advertises
> > IPv6 but does not handle it.
> 
> The correct way to deal with that is to put "ip6mode=host" into
> "/etc/rc.conf". That will stop your NetBSD system from accepting
> to advertised bogus IPv6 prefix.
> 
> > telnet smtp.iprimus.com.au 25
> > Trying 1.0.0.0...
> > telnet: Unable to connect to remote host: Connection timed out
> 
> What nameserver are you using? Is that your ISP nameserver or the
> builtin nameserver of a cheap router appliance? Some of the later
> kind can get confused if a client ask them for anything other
> than A records.
> 
> 	Kind regards
> 
> -- 
> Matthias Scheler                                  http://zhadum.org.uk/

Hi Matthias,

I am still not sure that a router falsely advertising IPv6 is the problem, I was supposing this might be the case,because of my previous problems with pkgsrc,(ftp timed out when trying  to retrieve pkg until I put the line 

FETCH_BEFORE_ARGS=-4

forcing pkgsrc to use IPv4)

Because of the strange thing with forcing telnet to use IPv4  temporarily allowing me to send mail, I thought it might be the same thing. 
I tried altering rc.conf as you suggested, but it made no difference, notice also that the same line already appeared in the startup messages after booting up.

Again I am not sure which nameserver I am using, how can I find out? The router I am using is an Open Iconnect Access 621 provided by my ISP so I imagine it is a cheap one. 

regards,

Alasdair