[exim] expansion contains non-digit

Hello-

I recently added an lsearch to perform a lookup for certain hosts and disable their SMTP limits:

smtp_accept_max_per_host = \
  ${lookup{$sender_host_address}lsearch{/etc/exim/hostlimits} {$value}\
     { ${lookup{${mask:$sender_host_address/24}}lsearch*{/etc/exim/hostlimits}} }\
  }

With the file /etc/exim/hostlimits containing:

192.168.1.25:    0
192.168.1.26:    0
*:               20

When send a test message from Gmail to my work account (hits the *: 20 line), I see this first line in the log complaining about the expansion containing a non-digit. The message still gets through, however. Is this anything to worry about?

2010-06-14 11:57:34 expansion of smtp_accept_max_per_host for [209.85.214.42] contains non-digit: 20
2010-06-14 11:57:35 1OOC2Z-0003sL-1Y DKIM: d=gmail.com s=gamma c=relaxed/relaxed a=rsa-sha256 [verification succeeded]
2010-06-14 11:57:35 1OOC2Z-0003sL-1Y <= my@??? H=mail-bw0-f42.google.com [209.85.214.42] P=esmtp S=1838 id=AANLkTik7Y6GwvOnMajJ52-
N09bkDVpgvs6P0sertC@???
2010-06-14 11:57:35 1OOC2Z-0003sL-1Y => test@??? R=to_spam_appliance T=remote_smtp H=192.168.1.3 [192.168.1.3] X=TLSv1:AES256-SHA:256
2010-06-14 11:57:35 1OOC2Z-0003sL-1Y Completed


Thanks,
Alex