[Exim] Delivery failure to fedex.com

One of my mail clients is trying to send mail to a person at fedex.com.  He
regularly gets bounces on most of the mail he sends out, but occasionally it
goes through.  It goes through when it tries the MX record with a 300
preference, but exim does not appear to regularly try this record.  Could
anyone help me out with this?

Here is what I have discovered so far in my examination:

1.  fedex.com has three MX records numbered from 100 to 300 in priority.
 They are
fedex.com       preference = 100, mail exchanger = mapper.mail.fedex.com
fedex.com       preference = 200, mail exchanger = smtp.zmd.fedex.com
fedex.com       preference = 300, mail exchanger = smtp.dmz.fedex.com

2.  All of the failures are Connection Refused, and they are to the first two
addresses. (mapper and zmd).

3.  All of the successful deliveries go through the last one, dmz.

4.  I am running with the default retry rule: * * F,2h,15m; G,16h,1h,1.5; F,4d,8h

5.  Exim does not appear to be paying attention to this retry rule.

Looking in the log file, I see exim sometimes giving up immediately after trying
the first two MX records:

2001-05-09 09:12:16 14xTlH-0007k0-00 <= xx@??? H=(xx) [x.x.x.x] P=asmtp A=login:xx@??? S=1215 id=004601c0d889$8a4a05c0$396417ac@xx
2001-05-09 09:12:16 14xTlH-0007k0-00 mapper.mail.fedex.com [199.81.10.25]: Connection refused
2001-05-09 09:12:16 14xTlH-0007k0-00 mapper.mail.fedex.com [199.81.10.26]: Connection refused
2001-05-09 09:12:16 14xTlH-0007k0-00 smtp.zmd.fedex.com [199.82.159.10]: Connection refused
2001-05-09 09:12:17 14xTlH-0007k0-00 smtp.zmd.fedex.com [199.82.159.11]: Connection refused
2001-05-09 09:12:17 14xTlH-0007k0-00 smtp.zmd.fedex.com [199.81.77.41]: Connection refused
2001-05-09 09:12:17 14xTlH-0007k0-00 == xx.xx@??? T=remote_smtp defer (111): Connection refused
2001-05-09 09:12:18 14xTlH-0007k0-00 => xx@??? R=lookuphost T=remote_smtp H=mx2.mail.yahoo.com [216.136.129.15]
2001-05-09 09:12:18 14xTlH-0007k0-00 ** xx.xx@???: retry timeout exceeded
2001-05-09 09:12:18 14xTlK-0007kI-00 <= <> R=14xTlH-0007k0-00 U=mail P=local S=2055
2001-05-09 09:12:18 14xTlH-0007k0-00 Error message sent to xx@???
2001-05-09 09:12:18 14xTlH-0007k0-00 Completed

Other times, it tries every hour until it eventually hits the smtp.dmz.fedex.com
address, at which point, it succeeds:

2001-04-23 17:17:07 14rnhj-0004Un-00 <= xx@??? H=(xx) [x.x.x.x] P=asmtp A=login:xx@??? S=2620 id=00af01c0cc3a$a144bd20$4ec5a518@xx
2001-04-23 17:17:07 14rnhj-0004Un-00 mapper.mail.fedex.com [199.81.10.26]: Connection refused
2001-04-23 17:17:08 14rnhj-0004Un-00 mapper.mail.fedex.com [199.81.10.25]: Connection refused
2001-04-23 17:17:11 14rnhj-0004Un-00 smtp.zmd.fedex.com [199.82.159.11]: Connection refused
2001-04-23 17:17:11 14rnhj-0004Un-00 smtp.zmd.fedex.com [199.81.77.40]: Connection refused
2001-04-23 17:17:11 14rnhj-0004Un-00 smtp.zmd.fedex.com [199.82.159.10]: Connection refused
2001-04-23 17:17:11 14rnhj-0004Un-00 == xx.xx@??? T=remote_smtp defer (111): Connection refused
2001-04-23 18:07:46 14rnhj-0004Un-00 mapper.mail.fedex.com [199.81.10.25]: Connection refused
2001-04-23 18:07:46 14rnhj-0004Un-00 mapper.mail.fedex.com [199.81.10.26]: Connection refused
2001-04-23 18:07:46 14rnhj-0004Un-00 smtp.zmd.fedex.com [199.82.159.11]: Connection refused
2001-04-23 18:07:46 14rnhj-0004Un-00 smtp.zmd.fedex.com [199.82.159.10]: Connection refused
2001-04-23 18:07:47 14rnhj-0004Un-00 smtp.zmd.fedex.com [199.81.77.41]: Connection refused
2001-04-23 18:07:47 14rnhj-0004Un-00 == xx.xx@??? T=remote_smtp defer (111): Connection refused
2001-04-23 19:07:47 14rnhj-0004Un-00 mapper.mail.fedex.com [199.81.10.25]: Connection refused
2001-04-23 19:07:47 14rnhj-0004Un-00 mapper.mail.fedex.com [199.81.10.26]: Connection refused
2001-04-23 19:07:47 14rnhj-0004Un-00 smtp.zmd.fedex.com [199.82.159.10]: Connection refused
2001-04-23 19:07:47 14rnhj-0004Un-00 smtp.zmd.fedex.com [199.81.77.41]: Connection refused
2001-04-23 19:07:47 14rnhj-0004Un-00 smtp.zmd.fedex.com [199.82.159.11]: Connection refused
2001-04-23 19:07:47 14rnhj-0004Un-00 == xx.xx@??? T=remote_smtp defer (111): Connection refused
2001-04-23 20:07:46 14rnhj-0004Un-00 mapper.mail.fedex.com [199.81.10.25]: Connection refused
2001-04-23 20:07:46 14rnhj-0004Un-00 mapper.mail.fedex.com [199.81.10.26]: Connection refused
2001-04-23 20:07:46 14rnhj-0004Un-00 smtp.zmd.fedex.com [199.82.159.10]: Connection refused
2001-04-23 20:07:47 14rnhj-0004Un-00 smtp.zmd.fedex.com [199.81.77.40]: Connection refused
2001-04-23 20:07:47 14rnhj-0004Un-00 smtp.zmd.fedex.com [199.81.77.41]: Connection refused
2001-04-23 20:07:47 14rnhj-0004Un-00 == xx.xx@??? T=remote_smtp defer (111): Connection refused
2001-04-23 21:07:50 14rnhj-0004Un-00 mapper.mail.fedex.com [199.81.10.26]: Connection refused
2001-04-23 21:07:50 14rnhj-0004Un-00 mapper.mail.fedex.com [199.81.10.25]: Connection refused
2001-04-23 21:07:50 14rnhj-0004Un-00 smtp.zmd.fedex.com [199.81.77.41]: Connection refused
2001-04-23 21:07:50 14rnhj-0004Un-00 smtp.zmd.fedex.com [199.82.159.10]: Connection refused
2001-04-23 21:07:50 14rnhj-0004Un-00 smtp.zmd.fedex.com [199.81.77.40]: Connection refused
2001-04-23 21:07:50 14rnhj-0004Un-00 == xx.xx@??? T=remote_smtp defer (111): Connection refused
2001-04-23 22:07:46 14rnhj-0004Un-00 smtp.zmd.fedex.com [199.82.159.11]: Connection refused
2001-04-23 22:07:48 14rnhj-0004Un-00 => xx.xx@??? R=lookuphost T=remote_smtp H=smtp.dmz.fedex.com [199.81.194.38]
2001-04-23 22:07:48 14rnhj-0004Un-00 Completed