[exim] Misconfigured DKIM whitelist?

I must be confused by the way my exim.conf works. I am getting DKIM
rejects like this:

2013-03-01 12:37:52 1UBUq7-0006qM-Pn H=(mail-wi0-f169.google.com)
[209.85.212.169] rejected DKIM : REJECTED - DKIM failure: pubkey_unavailable
2013-03-01 12:37:55 1UBUqB-0006qn-08 H=(mail-ia0-f180.google.com)
[209.85.210.180] rejected DKIM : REJECTED - DKIM failure: pubkey_unavailable


My exim.conf file has the following:

acl_check_dkim:
   accept authenticated  = *
   accept hosts          = :
   accept hosts          = +whitelisted_hosts
   deny message          = REJECTED - DKIM failure: $dkim_verify_reason
        #dkim_status      = none:invalid:fail
        dkim_status      = none:invalid
        condition        = ${if eq {$dkim_key_testing}{1} {no}{yes}}
   warn add_header       = X-DKIM: Status on $received_ip_address using 
Baruwa 2.0: dkim=$dkim_verify_status; \
                           signing_identity="$dkim_cur_signer"
   accept

+whitelisted_hosts points to the following:

hostlist whitelisted_hosts = WHITELISTED_HOSTS

WHITELISTED_HOSTS is part of my baruwa postgres database. Google.com,
googlemail.com and gmail.com have been added to the whitelist, yet get
bounced for DKIM problems.


Any ideas?