We are running GW 8.0.2 on NetWare 6.5.6. This error just started with this customer on 11/5/10. I tried researching, but did not find anything useful. the customer has tried whitelisting us in their spam filter. I'm not quite sure where to go from here.

15:54:23 28E MSG 3217602 Analyzing result file: ***/***:\***\WPGATE\GWIA\result\rcd2e326.274
15:54:23 28E MSG 3217602 Command: customer.com
15:54:23 28E MSG 3217602 Response: 220 server-10.tower-558.messagelabs.com ESMTP
15:54:23 28E MSG 3217602 Command: EHLO ***.pubpress.com
15:54:23 28E MSG 3217602 Response: 250 ok
15:54:23 28E MSG 3217602 Command: MAIL FROM:<***@pubpress.com>
15:54:23 28E MSG 3217602 Response: 250 MAIL FROM accepted
15:54:23 28E MSG 3217602 Detected error on SMTP command
15:54:23 28E MSG 3217602 Command: RCPT TO:<***@customer.com>
15:54:23 28E MSG 3217602 Response: 421 Service Temporarily Unavailable
15:54:23 28E MSG 3217602 Deferring message: ***/***:\***\WPGATE\GWIA\defer\scd2e326.274

Thanks,
Bill