[Exim] "exim -bh" and "require verify = sender" don't play n…

Hi all,

I'm new to this list and I've only been using exim for 6 months so please
don't flame me for what might be a silly question :-)

I start an "exim -bh" fake SMTP session on my server, specifying the IP of the
firewall I am behind (ie the IP address that exim sees in a genuine SMTP
session from my current location). "Mail From" is the address I am writing
this email from (which routes to a local user on my server). Then, any "Rcpt
To" command is rejected "451 Temporary local problem" because sender verify
failed. If I telnet in from my current location (ie a real SMTP session) and
issue _exactly_ the same commands, the Rcpt is accepted.

I know this is to do with the "require verify = sender" line in the config
because if I comment this line out, then the message is accepted.

Why can't exim verify a local mail address when run in test mode? Am I missing
something really obvious, or is exim ? ;-) I'm using version 4.00.

TIA
Rich