[Exim] Broken Aliases after upgrading from Exim3 to Exim4

Hi,
I recently upgraded from Exim 3 to Exim 4.2x
my problem is I have 1 e-mail account for my domain I treat as an
alias. It for a user who never needed POP access. I just added his
name to the /etc/aliases files to redirect his e-mail to his e-mail
address at his ISP. I never needed to create a physical account for
him.

Under Exim 3 it worked like a charm. But I just noticed that under
Exim 4 it is broken.
Messages for root are redirected to my personal account, and those
work, but every message addressed to the aliased e-mail fails.

I get the following error.
Delivery has failed on the enclosed message for the following
reasons reported either by the mail delivery system on the mail
relay host or by the local TCP/IP transport module:

451 Temporary local problem - please try later

The Exim4 log has this entry

2003-11-02 12:25:21 H=(win95) [192.168.62.73] F=<dean@???>
temporarily rejected RCPT <john@???>: host lookup did not
complete

I have checked my exim4 conf.d and I have the following router entry
in /etc/exim4/conf.d/router/400_exim4-config_system_aliases
system_aliases:
debug_print = "R: system_aliases for $local_part@$domain"
driver = redirect
allow_fail
allow_defer
data = ${lookup{$local_part}lsearch{/etc/aliases}}
# user = list
file_transport = address_file
pipe_transport = address_pipe
# directory_transport = address_directory


and my aliases file is /etc/aliases writeable by root only, and
readable by all.

Can anyone shed some light on where to look to fix this issue.
Also, in case it is pertinent, I am also running Spamassassin and sa-
exim. is it possible that sa-exim or Spamassassin are causing the
problem?

Thanks
Dean
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Dean Staff Kanata On. Canada
A+, MCP, MCSA, MCSE, CIW Security Analyst
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